JPH09124912A - Thermoplastic polyester resin composition and molded article made therefrom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic polyester resin composition having uniform properties and excellent in such characteristics as water repellency and impact resistance in particular, and a molded article made therefrom. SOLUTION: This composition comprises a thermoplastic polyester (A), a polytetrafluoroethylene (B) and a polyvinylidene fluoride copolymer (C) having a melt flow rate (230 deg.C, 2.16kg) of at most 500, wherein the component A and the total of components B and C account for 60-99.5wt.% and 40-0.5wt.% respectively of the total weight of components A, B and C, and the weight ratio of component B to component C is (10:1) to (1:10).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermoplastic polyester resin composition and a molded article thereof. The object thereof is to provide a thermoplastic polyester resin composition excellent in uniform performance, particularly in moldability, water repellency, impact resistance, slipperiness, abrasion resistance and the like, and a molded article thereof. .

[0002]

2. Description of the Related Art Thermoplastic polyester resins represented by polybutylene terephthalate and polyethylene terephthalate (hereinafter abbreviated as PBT and PET, respectively) have mechanical properties, chemical resistance, heat resistance and crystallinity. It has excellent weather resistance and is widely used in industrial resins, films, fibers, containers and the like. However, the molded product is apt to be dirty or susceptible to moisture, or the slip between products is bad, which causes a problem in process or use.

In order to improve these, it is known to blend a fluororesin. For example, JP-A-62-2
In Japanese Patent No. 38822, it is proposed to blend PET with a fluorine resin having a melting point of 280 ° C. or lower. Specifically, ethylene tetrafluoride ethylene copolymer and polyvinylidene fluoride (hereinafter abbreviated as ETFE and PVDF) are exemplified, but it is necessary to use PET having a high degree of polymerization in order to improve the kneading property. In addition, JP-A-2-2691
No. 9 discloses that a fluororesin is dispersed in a polyester, a polyamide, an acrylic resin or the like in order to improve slipperiness and stain resistance. As the fluorine-based resin, it is described that various polymers are included in the general formula, but specifically, the effect has been confirmed only with polytetrafluoroethylene, and two or more kinds of fluorine-based resins are included. No mention is made of complex systems. Further, JP-A-6-
No. 136616 discloses that polyester has a melting point of 100 to 2
It is disclosed to contain a fluorine-based resin at 80 ° C. Specifically, only ETFE and PVDF are mentioned, as in the above-mentioned JP-A-62-238822.

Fluorine-based resins are essentially incompatible with polyesters, and there is a limit when they are used under severe conditions such as industrial resins simply by blending. As a method of improving this, a ternary composition with an olefinic compatibilizer having a specific functional group has been proposed (JP-A-7-
18144). Certainly the elongation and impact strength are improved, but this is mainly composed of fluororesin,
It is not always sufficient from the viewpoint of modifying the polyester.

[0005]

The present invention is to improve the moldability, water repellency, impact resistance, abrasion resistance, etc. of a polyester resin. A polyester resin is obtained by combining two or more kinds of fluororesins. By blending it, this object could be achieved.

[0006]

The present invention is directed to a thermoplastic polyester (A), polytetrafluoroethylene (B) and a melt flow rate (230 ° C., 2.16 kg) 500 or less polyvinylidene fluoride copolymer ( C) consists of
(A) 60 relative to the total weight of (A), (B) and (C)
~ 99.5% by weight and the sum of (B) and (C) is 40 ~
0.5% by weight and (B) / (C) 10/1 by weight ratio
It is a thermoplastic polyester resin composition characterized by being 1/10, and its molded article.

In the present invention, "thermoplastic polyester resin (A)" means polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyhydroxyethoxybenzoate. Etc., but a small amount, for example, 10
Isophthalic acid, 5-sodium sulfoisophthalic acid, adipic acid, diethylene glycol in a proportion of not more than mol%,
It may be a copolymer of propylene glycol, 1,4-cyclohexane dimethanol, polyoxyethylene, polyoxytetramethylene (the last two have 1 mol of repeating units) and the like. Further, trifunctional or higher functional compounds having a substantially linear molecule, for example, trimellitic acid, trimesic acid, pyromellitic acid, glycerin, trimethylolpropane, pentaerythritol and the like can be used.

In the present invention, "polytetrafluoroethylene (B)" is a powdery polymer containing at least 95% by weight of tetrafluoroethylene as a constitutional unit of a resin and has a melting point of 300.degree. The above is said. Melting point 300
If it is less than 0 ° C, it becomes difficult to control the dispersed state when the composition with polyester is prepared in a molten state. The preferable average particle diameter of the powder is generally 10 μm or less, preferably 1 μm or less, though it varies depending on the use.

In the present invention, the "polyvinylidene fluoride copolymer (C)" means 20% by weight or more, preferably 30% by weight or more of vinylidene fluoride as a constitutional unit of resin.
More preferably, it is a polymer containing 50% by weight or more.
As a copolymerizable component, tetrafluoroethylene (hereinafter T
(Abbreviated as FE), ethylene trifluoride, ethylene trifluoride chloride (CTFE), vinyl fluoride (VF), propylene hexafluoride (HFP), ethylene, perfluoroalkyl vinyl ether, and the like. . Of these, TF
A ternary terpolymer containing two or more copolymerization components containing E is particularly preferable. The present polyvinylidene fluoride copolymer is obtained by a commonly used polymerization method such as emulsion polymerization and suspension polymerization, and has an MFR value of 500 g / 10 minutes or less. MF in the case of binary copolymer
R0.1-50, MFR1 in the case of a ternary copolymer
It is preferably 400 g / 10 minutes.

In the composition of the present invention, the blending ratio of the thermoplastic polyester (A) to the polytetrafluoroethylene (B) and the polyvinylidene fluoride copolymer (C) is (A),
(A) 6 for 100 parts by weight of the total of (B) and (C)
0-99.5% by weight, and (B) + (C) 40-0.5
% By weight. When the proportion of (A) is less than 60% by weight, the purpose of modifying the polyester resin of the present invention is defeated, and when the proportion of (B) + (C) is less than 0.5% by weight of the present invention. The modification purpose cannot be achieved. (B) /
The weight ratio of (C) is 10/1 to 1/10.
When the ratio of (B) exceeds the upper limit, the dispersion in the polyester becomes poor, and when it is less than the lower limit, the performance such as water repellency deteriorates. The weight ratio of (B) / (C) is preferably 10/2 to
It is 5/5.

The composition of the present invention can be directly molded by dry blending each resin in a predetermined ratio, but the resins (A), (B) and (C) can be melt-kneaded before molding. Preferably, (B) and (C) are mixed in advance. The melt kneading can be performed by a conventionally known method. For example, using a Banbury mixer, a rubber roll machine, a single-screw or twin-screw extruder, or the like, usually 240 to 300 ° C., preferably 260 to 290 ° C. depending on the composition (in the case of mixing only B and C,
100 to 300 ° C, preferably 150 to 300 depending on the composition
A resin composition can be obtained by melt-kneading at a temperature of 260 ° C.). In the case of using an extruder, the screw tip may be of dullage type in order to increase the degree of kneading, a reverse phase mixing disk may be placed in the center of the screw, and a static mixer may be attached to the tip.

The composition of the present invention can be molded into fibers, films, sheets, pipes, tubes and the like in addition to ordinary injection molded products. The form of fiber includes multifilament, monofilament, staple, woven fabric,
It can be a knitted fabric, a non-woven fabric, or the like, and the cross-sectional shape of the fiber can be any conventionally known one such as solid, hollow, and irregular shape. The form of the film may be a film, a sheet, a plate, or the like.

The composition of the present invention includes a conventionally known antioxidant, thermal decomposition inhibitor, ultraviolet absorber, hydrolysis resistance improver,
Colorant (dye, pigment), antistatic agent, conductive agent, crystal nucleating agent, crystal accelerator, plasticizer, lubricant, lubricant, release agent, flame retardant, flame retardant aid, reinforcing agent, filler, Adhesion aids, pressure-sensitive adhesives and the like can be optionally contained.

[0014]

The composition of the present invention has uniform performance, especially water repellency,
As a thermoplastic polyester resin composition excellent in impact resistance, slipperiness, abrasion resistance, etc., it is useful as a material for injection molded products, fibers, films and the like.

[0015]

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples, but it goes without saying that the present invention is not limited to these examples. Incidentally, various test pieces and characteristics in the examples were prepared, measured and evaluated by the following methods. (1) Intrinsic viscosity of polyester It was calculated from the solution viscosity of a 1.2 g / dl o-chlorophenol solution of the polymer at 35 ° C. (2) Melt Index (MFR) of Vinylidene Fluoride Copolymer According to ISO1133, it was measured at 230 ° C. under a load of 2.16 kg. Unit g / 10 minutes. (3) Preparation of Composition A powder of a polytetrafluoroethylene / vinylidene fluoride copolymer or pellets is put in a blender in a predetermined amount and mixed, and then strands are formed using a uniaxial extruder set to a cylinder temperature of 160 to 260 ° C. And extruded into pellets. Next, the pellets were dry-blended with polyester at a predetermined ratio, and then extruded from a uniaxial extruder set at 285 ° C., and pelletized to obtain a molding composition. (4) Manufacture of molded product 80x10x4 mm, and 100x10 with the injection molding machine of 80 tons of mold clamping force which set the said composition at 275 degreeC.
A 0x4 mm test piece was prepared. (5) Water repellency From a height of 10 mm on a flat plate of 100 × 100 × 4 mm,
1 μl of distilled water was dropped, and the contact angle after 10 seconds was used as a measure of water repellency. (6) Impact strength Using a test piece of 80 × 10 × 4 mm, ISO18
It was measured by 0 / 1A. (7) Uniformity of quality In the above-mentioned water repellency measurement, the quality was determined by the coefficient of variation of the values measured at 10 mm intervals in the vertical and horizontal directions (percentage relative to the average value of standard deviation) and the coefficient of variation when the impact strength was measured at n = 10. Of uniformity.

Abbreviations and contents of each polymer used in this example are as follows. PBT: Polybutylene terephthalate having an intrinsic viscosity of 0.78. PET: polyethylene terephthalate with an intrinsic viscosity of 0.64
G. PTFE: Polytetrafluoroethylene with an average particle size of 0.5μ. PVDF-1: VDF / TFE / HFP in a weight ratio of 60
/ 25/15 MFR200 ternary PV
DF copolymer. PVDF-2: VDF / TFE / HFP in a weight ratio of 30
/ 50/20 MFR4 ternary PVDF
Copolymer. PVDF-3: PVDF copolymer of MFR3 with a VDF / TFE weight ratio of 70/30. PVDF-4: PVDF copolymer of MFR 0.5 with a VDF / HFP weight ratio of 85/15.

[0017]

Example 1 Polyester, PTFE and PVDF copolymer were blended in the proportions shown in Table 1 and molded. The quality of the obtained molded product is as shown in the right column of the table. It can be seen that the composition of the present invention is not only excellent in water repellency and impact resistance, but also has a uniform quality with little variation. Further, when the molded article of Example 2 and the molded article of Comparative Example 1 were cooled with liquid nitrogen and divided, the cross sections were observed with a scanning electron microscope.
It was found that the fluororesin of Example 2 was finely and uniformly dispersed in PET as compared with that of Comparative Example 1.

[0018]

[Table 1]

[0019]

As described above, the composition of the present invention is not only excellent in water repellency, impact resistance, etc., but also has little variation in quality, and is excellent as an injection molded product, fiber, film, etc. It is a material.

Front page continuation (72) Kazuyoshi Ohashi, Kazuyoshi Ohashi, 1 Awata-cho, Nakado-ji, Shimogyo-ku, Kyoto, Japan Elf Atchem Japan Co., Ltd. Kyoto Technical Center (72) Kuniyuki Goto 3-chome, Urawa-shi, Saitama 12 No. 2 Cosmo Musashi Urawa 306

Claims (4)

[Claims] 1. A thermoplastic polyester (A), a polytetrafluoroethylene (B) and a melt flow rate (230).
(C, 2.16 kg) consisting of a polyvinylidene fluoride copolymer (C) of 500 or less, and (A) 60 to 99.5% by weight and (A) based on the total weight of (A), (B) and (C). B)
And (C) total 40 to 0.5% by weight, and (B) /
(C) is a weight ratio of 10/1 to 1/10, The thermoplastic polyester resin composition characterized by the above-mentioned. 2. The thermoplastic polyester resin composition according to claim 1, wherein the polyvinylidene fluoride copolymer (C) is a copolymer containing ethylene tetrafluoride and / or propylene hexafluoride. 3. A thermoplastic polyester (A), a polytetrafluoroethylene (B) and a melt flow rate (230).
(C, 2.16 kg) consisting of a polyvinylidene fluoride copolymer (C) of 500 or less, and (A) 60 to 99.5% by weight and (A) based on the total weight of (A), (B) and (C). B)
And (C) total 40 to 0.5% by weight, and (B) /
(C) is a weight ratio of 10/1 to 1/10, which is a molded product of a thermoplastic polyester resin composition. 4. The molded article is an injection molded article, a fiber, a sheet,
The thermoplastic polyester resin molded article according to claim 3, which is one selected from the films.