JP3107918B2 - Polyester resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the development of a polyester resin molding material exhibiting excellent tracking resistance by combining at least two specific polymers in a specific amount with a polyester resin.

[0002]

2. Description of the Related Art Polyester resins represented by polyethylene terephthalate (hereinafter abbreviated as PET) and polybutylene terephthalate (hereinafter abbreviated as PBT) have strength, toughness, chemical resistance, and electrical insulation properties. It is widely used as an engineering plastic in electric / electronic parts, automobile parts, mechanical parts, etc.
Utilizing particularly excellent electrical properties, it is used as a material for various electrical components such as relay cases, capacitor cases, transformer bobbins, and connectors. However, the tracking resistance of these polyester resins is different from other resins, for example, polyolefins such as polyethylene and polypropylene, polyamides such as nylon 6, nylon 66, and thermosetting resins such as unsaturated polyester, fluororesin, and melamine resin. It is hard to say that it is always superior to the above. Furthermore, it is known that when glass fibers, certain coloring agents, and other additives are blended for the purpose of improving other properties of these polyester resins, their tracking resistance is further reduced. In spite of the demand for the use of useful properties, they are often not used as component materials due to poor tracking resistance.

The inventor of the present invention has made intensive studies to improve the essential disadvantages of the polyester resin, and has reached the present invention.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the tracking resistance while maintaining the excellent characteristics of a polyester resin as much as possible.

[0005]

The present inventors have made intensive studies to improve the tracking resistance of a polyester resin, and as a result, have found that the above-mentioned objects are met by combining at least two types of specific polymers in specific amounts. The present invention has been reached. That is, the polyester resin composition of the present invention comprises (A) 100 parts by weight of the polyester resin (B)
1 to 30 parts by weight of a thermoplastic elastomer and (C)
A polyester resin composition comprising 1 to 30 parts by weight of a polyolefin. Hereinafter, the present invention will be described in detail.

The polyester resin of the component (A) used in the present invention means that terephthalic acid or 2,6-naphthalenedicarboxylic acid or an ester-forming derivative thereof is used as a main acid component, and the main glycol component has 2 to 2 carbon atoms. The present invention is directed to a linear saturated polyester obtained by using a glycol of 10 or an ester-forming derivative thereof, for example, polyethylene terephthalate (PET),
Examples include polypropylene terephthalate, polybutylene terephthalate (PBT), polyhexamethylene terephthalate, polycyclohexane 1,4-dimethylene terephthalate, polybutylene 2,6-naphthalenedicarboxylate (PBN), and the like. Among them, especially PE
T, PBT and PBN are preferred.

[0007] The term "principal" as used herein means at least 80 mol%, preferably at least 90 mol%, based on all acid components or all glycol components. These polyesters may be used alone or as a mixture of two or more.

[0008] Further, the acid component or the glycol component may be partially replaced with another copolymer component. Such copolymerizable acid components include terephthalic acid and 2,6-
Aromatic dicarboxylic acids other than naphthalenedicarboxylic acid, such as isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenyl ether dicarboxylic acid,
Diphenoxyethane dicarboxylic acid, diphenyl ketone dicarboxylic acid, diphenyl sulfone dicarboxylic acid, etc., aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, etc., alicyclic dicarboxylic acids such as cyclohexane dicarboxylic acid, tetralin dicarboxylic acid, decalin dicarboxylic acid Acids and the like are exemplified. Examples of copolymerizable glycol components other than glycols having 2 to 10 carbon atoms include tricyclodecane dimethylol, bisphenol A, bisphenol B, bishydroxyethoxybisphenol A, and the like.

Further, a polyfunctional compound such as glycerin,
Trimethylolpropane, pentaerythritol, trimellitic acid, pyromellitic acid and the like may be copolymerized.

[0010] The thermoplastic elastomer as the component (B) of the present invention refers to a polyalkylene oxide as one component.
It can be produced by combining and reacting a dicarboxylic acid component and, if necessary, a glycol component.

The polyalkylene oxide is a polymer comprising alkylene oxide units having 2 to 4 carbon atoms. Examples of the alkylene group include ethylene, trimethylene and tetramethylene groups.
Specific examples of the polyalkylene oxide include poly (ethylene oxide), poly (propylene oxide), and poly (tetramethylene oxide). The polyalkylene oxide has a molecular weight of 200 or more, preferably 5
00 or more, for example, poly (ethylene oxide) having a molecular weight of 1,000 or poly (tetramethylene oxide) having a molecular weight of 1,000.

Examples of the dicarboxylic acid component include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid,
4-cyclohexanedicarboxylic acid, adipic acid, sebacic acid and the like can be mentioned. Examples of the glycol component include ethylene glycol, 1,2-propanediol, 1,4-butanediol, 1,6-hexanediol, and 1,4-cyclohexanedimethanol. Such a polyester elastomer is 500
It is preferable to have the above molecular weight.

The amount of these polyester elastomers is 1 to 30 parts by weight per 100 parts by weight of the polyester resin. When the amount is less than 1 part by weight, the effect of improving the tracking resistance, which is an improvement effect of the present invention, is small. On the other hand, when the amount of orientation is more than 30 parts by weight, the excellent heat resistance and fluidity inherent to the polyester resin. And other properties are impaired.

The polyolefin constituting the component (C) of the present invention refers to a polymer produced by an ordinary method using an olefin such as ethylene, propylene, butene-1, or pentene-1 as a monomer. These olefins can be used alone or in combination of two or more. Further, if necessary, copolymerization with another monomer having a double bond of 10% by weight or less is also possible. Examples of these copolymerizable monomers include vinyl acetate, isoprene, chloropyrene, butadiene, etc., monocarboxylic acids such as acrylic acid and methacrylic acid and derivatives thereof such as acid anhydrides and glycidyl esters, maleic acid, fumaric acid, itacone Examples thereof include dicarboxylic acids such as acids and acid anhydrides thereof. The most preferred of these polyolefins are polyethylene and polypropylene.

The addition amount of these polyolefins is 1 to 30 parts by weight per 100 parts by weight of the polyester resin. When the amount is less than 1 part by weight, the effect of improving the tracking resistance, which is an improvement effect of the present invention, is small. On the other hand, when the amount of orientation is more than 30 parts by weight, the excellent heat resistance and fluidity inherent to the polyester resin. And other properties are impaired.

If desired, the polyester resin composition of the present invention may contain other additives such as a stabilizer, a colorant, an ultraviolet absorber, a release agent, an antistatic agent, and a crystallization within a range that does not significantly impair the properties of the polyester resin composition. Accelerators, crystalline nucleic acids, fillers, impact modifiers, flame retardants and the like can be added.

To obtain the resin composition according to the present invention, any compounding method can be used. Usually, it is preferable that these components are more uniformly dispersed, and all or a part thereof is simultaneously or separately, for example, a blender.
A method of mixing and homogenizing with a mixer such as a kneader, a Banbury mixer, a roll, and an extruder, or mixing a part of the mixed portion simultaneously or separately with, for example, a blender, a kneader, a mixer, a roll, an extruder, and the like. Can be used by mixing and homogenizing the above components with these mixers or extruders. Further, there is a method in which a composition which has been dry-blended in advance is melt-kneaded with a heated extruder, homogenized, extruded into a wire, and then cut into a desired length to granulate.

The resin composition obtained according to the present invention can be molded very easily by a usual method using a general thermoplastic resin molding machine.

[0019]

The present invention will be described in detail with reference to the following examples. In addition,
Various properties in the examples were measured by the following methods. (1) Mechanical strength:-Tensile test: in accordance with ASTM D638. -Impact test (1/8 "thickness, with Izod notch)
…… Conforms to ASTM D256. In addition, the test piece for a measurement used the molded article based on the above-mentioned ASTM test. (2) Tracking resistance test • IEC Publ. 112 (3rd edition)-1979
Compliant with.

Test solution A (ammonium chloride) is used.・ Indicated by the comparative tracking index (CTI). In addition, the test piece for a measurement used the disk molded product of diameter 50mm and thickness 3mm.

[0021]

Examples 1 to 4 and Comparative Examples 1 to 7 Various raw materials shown in Table 1 were uniformly mixed in a predetermined amount in advance by a tumbler, and then evacuated using a vented single screw extruder having a screw diameter of 68 mm. While kneading at a cylinder temperature of 280 ° C., a screw rotation speed of 64 rpm, and a discharge rate of 55 kg / h,
The thread discharged from the die was cooled and cut to obtain a molding pellet.

Next, using the pellets, an injection molding machine having an injection capacity of 5 oz. Was used for an injection pressure of 800 kg / cm ² , a cooling time of 15 seconds, and a test for strength measurement and tracking resistance measurement under the conditions of a total molding cycle of 40 seconds. Pieces were molded and subjected to measurements.

The following raw materials were used as shown in Table 1. PET: PETTR8550 PBT manufactured by Teijin Limited PBT TRB-J PBN manufactured by Teijin Limited PBN C8000 manufactured by Teijin Limited Glass fiber: 3PE474 manufactured by Nitto Boseki Release agent: Hoechst WAX manufactured by Hoechst -E talc: PKNN HY manufactured by Hayashi Kasei Co., Ltd .: Polyether-ester based elastomer Hytrel 4056 PE-1 manufactured by DuPont Co., Ltd. Polyethylene HIZEX Million 145M PE-2 manufactured by Mitsui Petrochemical Industry Co., Ltd. Nihon Unicar ( Co., Ltd. Polyethylene D
ND-2450 PP-1 ... polypropylene Noblen JS-G PP-2 manufactured by Mitsui Toatsu Chemicals Co., Ltd. polypropylene polypropylene Noblen BJHH-G manufactured by Mitsui Toatsu Chemicals Co., Ltd. Flame retardant ... bromine flame retardant manufactured by Teijin Chemicals Ltd. FG7
100 Flame retardant aid: Antimony trioxide manufactured by Nippon Seimitsu Co., Ltd.
ATOX-S As is clear from the results in Table 1, the tracking resistance of the polyester resin is remarkably improved by the synergistic effect of the components (B) and (C) of the present invention.

[0024]

[Table 1]

Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 67/00-67/08 C08L 23/00-23/24

Claims (4)

(57) [Claims] A polyester resin composition comprising (A) 1 to 30 parts by weight of a thermoplastic elastomer and (C) 1 to 30 parts by weight of a polyolefin per 100 parts by weight of a polyester resin. 2. The polyester resin composition according to claim 1, wherein the polyester resin is polybutylene terephthalate. 3. The polyester resin composition according to claim 1, wherein the polyester resin is polyethylene terephthalate. 4. The polyester resin composition according to claim 1, wherein the polyester resin is polybutylene naphthalenedicarboxylate.