KR20060035119A - Polybutylene terephthalate resin composition and multi-layer insulating electric wire comprising the same - Google Patents

Abstract

The present invention is 50-95% by weight of polybutylene terephthalate, 1-30% by weight of polyester elastomer, 1-20% by weight of styrene-ethylene-butadiene-styrene copolymer, and 0.5-10% by weight of titanium dioxide Modified polybutylene terephthalate resin composition comprising a; And a conductor, at least one first covering layer made of the resin composition, and a second covering layer formed of polyamide on the covering layer. The modified polybutylene terephthalate resin composition according to the present invention has a flowability and extrudability suitable for the production of insulated wire, the wire produced therefrom is excellent in appearance uniformity, hydrolysis resistance, heat resistance, wear resistance and insulation Do.

Polybutylene Terephthalate, Styrene-Ethylene-Butadiene-Styrene Copolymer, Insulated Wire, Polyester Elastomer, Titanium Dioxide

Description

Polybutylene terephthalate resin composition and multi-layer insulated wire manufactured using the same {Polybutylene Terephthalate Resin Composition and Multi-layer Insulating Electric Wire Comprising the Same}

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view of a multilayer insulated wire comprising a conductor, two layers of coating layers made of the polybutylene terephthalate resin composition according to the present invention, and a polyamide coating layer.

2 is a schematic flowchart of a multi-layered insulated wire manufacturing process according to the present invention.

Explanation of Drawing References

1. Conductor 2. Polybutylene terephthalate resin first coating layer

3. Polybutylene terephthalate resin second coating layer 4. Polyamide coating layer

5. Insulated wire 6. First extruder 7. Second extruder

8. Third Extruder 9. First Cooling Zone 10. Second Cooling Zone

11. Third cooling zone 12. Winch capstan 13. Winder

The present invention relates to a multilayer insulated wire comprising a modified polybutylene terephthalate resin composition and an insulating coating layer formed therefrom. More specifically, the present invention relates to a multi-layered insulated wire having excellent uniformity, heat resistance, abrasion resistance, and insulation of electric wire appearance having a modified polybutylene terephthalate resin composition having excellent flowability and extrudability and an insulating coating layer formed therefrom. will be.

Conventional polyesters used as an insulating coating material is a crystalline resin, flowability, extrudability is uneven, there were a number of problems due to this. In particular, the insulation coating layer of the wire produced due to the nonuniformity of the extrusion amount is not uniform, and thus the insulation and heat resistance are poor and easily deformed according to the temperature change, resulting in poor workability. On the other hand, with the tendency of miniaturization of electric and electronic equipment using high-electronic products and high frequency in recent years, insulated wires used in small products require electrical stability and strengthening of the insulating layer.

In addition, electronic products such as personal computers 'AC adapters, cell phones' batteries and monitors, printers, and VTR cameras are becoming smaller and higher in performance. Accordingly, there is an increasing need for multilayer insulated wires having better heat resistance, insulation, and uniformity than externally used multilayer insulated wires.

Therefore, the inventors have modified the polybutylene terephthalate resin composition obtained by mixing polybutylene terephthalate, polyester elastomer, styrene-ethylene-butadiene-styrene copolymer, and titanium dioxide in an appropriate ratio as an insulating coating layer. It was found that the insulated wire manufactured by using the present invention further improved various physical properties required by the insulated wire and completed the present invention.

 An object of the present invention is to provide a polybutylene terephthalate resin composition excellent in flowability and extrudability.

Another object of the present invention is to provide a multilayer insulated wire having a uniform appearance and excellent heat resistance, abrasion resistance and insulation.

It is still another object of the present invention to provide a resin composition for multilayer insulated wire coating comprising polybutylene terephthalate as a main component.

It is still another object of the present invention to provide an extrusion molded article made of the modified polybutylene terephthalate resin composition.

The above and other objects of the present invention can be achieved by the present invention described below.

The present invention provides a multilayer insulated wire having a modified polybutylene terephthalate resin composition and an insulating coating layer formed therefrom.

According to the first aspect of the invention, 50-95% by weight of polybutylene terephthalate, 1-20% by weight of styrene-ethylene-butadiene-styrene copolymer, 1-30% by weight of polyester elastomer, and titanium A polybutylene terephthalate resin composition composed of 0.5-10% by weight of dioxide is provided.

The polybutylene terephthalate resin composition is used as an extrusion product such as a tube, a film, an electric wire, and is particularly preferably used for coating an insulated wire.

According to a second aspect of the invention,

Conductor;

50-95% by weight of polybutylene terephthalate, 1-20% by weight of styrene-ethylene-butadiene-styrene copolymer, 1-30% by weight of polyester elastomer, and 0.5-10% by weight of titanium dioxide A first coating layer having a single layer or multiple layers made of a polybutylene terephthalate resin produced by polymerization; And

Second coating layer consisting of polyamide:

A multi-layered insulated wire is provided.

Hereinafter, the present invention will be described in more detail.

Modified polybutylene terephthalate resin composition according to the first aspect of the present invention is 50-95% by weight of polybutylene terephthalate, 1-30% by weight of polyester elastomer, styrene-ethylene-butadiene-styrene airborne 1-20% by weight of coal, and 0.5-10% by weight of titanium dioxide.

When the polybutylene terephthalate, styrene-ethylene-butadiene-styrene copolymer, polyester elastomer and titanium dioxide are added and kneaded and extruded with a twin screw extruder at a temperature of 240 to 280 ° C. Modified polybutylene terephthalate resins are prepared. The kneading extrusion process for producing a resin can be easily carried out by those skilled in the art.

The modified polybutylene terephthalate resin prepared as described above is improved in workability by improving the physical properties required in an insulated wire including flowability, extrusion property, uniformity of appearance, heat resistance, wear resistance, and insulation. In the present invention, the flowability refers to fluidity suitable for wire production, and refers to flowability (fluidity) that does not affect the melt tension of the polymer, the melt behavior of the polymer in the extruder, and the wire outer diameter. .

The polybutylene terephthalate (PBT), which is the main component of the resin composition according to the present invention, has a melting temperature of 220 to 240 ° C., and an intrinsic viscosity of IV (0.7) to 1.3 dl / g, preferably 0.75 to 1.2. Use PBT with dl / g. If the IV of PBT is less than 0.7dl / g, it is difficult to extrude. If it exceeds 1.3dl / g, it is different from other additives such as styrene-ethylene-butadiene-styrene copolymer and polyester elastomer. Due to phase separation or deterioration of properties.

The amount of PBT used in the resin composition according to the present invention is preferably 50 to 95% by weight based on the resin composition. If the PBT content in the resin composition is less than 50% by weight, it is difficult to play a role of the dispersing phase, and thus loses the inherent properties of the polybutylene terephthalate.When it is used in excess of 95%, the flowability during the high-speed extrusion process is too low, resulting in poor appearance Problem occurs.

As for the styrene-ethylene-butadiene-styrene copolymer, it is preferable to use 1-20 weight% with respect to a resin composition. When the styrene-ethylene-butadiene-styrene copolymer is used in excess of 20% by weight, the shrinkage is severe after molding, so that the thickness of the insulated wire is not uniform, and the styrene-ethylene-butadiene-styrene copolymer is 1 When used in an amount of less than% by weight, there is a problem in compatibility between the polybutylene terephthalate and the polyester elastomer, thereby causing a phase separation phenomenon, which adversely affects the electrical properties of the insulated wire. Preferably, the copolymer has a hardness (Shore-A) of 70 to 80 and a flowability of 10 to 15 g / min at a load of 230 ° C. and 10 Kg.

Polyester elastomers are thermoplastic polymers in which hard hard segments and soft soft segments are block copolymerized. Generally, aromatic dicarboxylic acid (Aromatic Dicarboxylic Acid) is used as the hard segment component, and lower diol or polyalkylene oxide (Polyalkylene Oxide) is used as the soft segment.

As aromatic dicarboxylic acid, for example, terephthalic acid (TPA), isophthalic acid (IPA), 1,5-dinaphthalenedicarboxylic acid (1,5-Dinaphthalenedicarboxylic acid, 1,5-NDCA ), 2,6-Dinaphthalenedicarboxylic acid (2,6-NDCA) and dimethyl terephthalate, which is an aromatic dicarboxylate substituted by a dimethyl group with a diacid. , Hereinafter referred to as DMT), dimethyl isophthalate or a mixture thereof, preferably DMT.

As the lower diol, ethylene glycol, propylene glycol, 1,4-butane diol, 1,5-pentanediol, 1,6-hexanediol, or 1,4-cyclohexanedimethanol is used. Preferably, 1, 4- butanediol is used. As polyalkylene oxide, polyoxyethylene glycol, polyoxypropylene glycol or polyoxytetramethylene glycol (PTMEG) is used, and preferably PTMEG is used. do.

In addition, it is possible to use a branching agent to increase the melt tension of the polyester elastomer to improve the stability during insulation wire extrusion to increase the insulation. Glycerol, pentaerythritol, neopentyl glycol, or the like is used as the branching agent, and glycerol is preferably used.

The amount of polyester elastomer used in the resin composition according to the present invention is preferably 1-30% by weight based on the resin composition. When the amount of use exceeds 30% by weight, phase separation with polybutylene terephthalate occurs, which adversely affects the extrudability and flowability of the insulated wire. If the amount is less than 1% by weight, the elasticity of the modified polybutylene terephthalate resin composition is reduced, the extrusion amount is not constant during the insulation wire processing, the insulation layer of the insulated wire becomes nonuniform.

In the present invention, it is preferable to use 0.5-10% by weight of titanium dioxide with respect to the resin composition for the electrical properties of the insulated wire. When the titanium dioxide is used at less than 0.5% by weight, discoloration of the insulated wire is severely generated. When the titanium dioxide is used at more than 10% by weight, cracking is severely generated on the outside of the insulated wire, causing problems in electrical characteristics of the insulated wire.

In addition, the composition according to the present invention may further include a heat stabilizer of aromatic amine, phenol, thioester (Thioester) or phosphite (Phosphite). It is preferable to use 0.1-5 weight% of the heat stabilizer in the resin composition of this invention, and the said content is the quantity generally used.

The modified polybutylene terephthalate resin obtained in accordance with the present invention is excellent in voltage resistance, heat resistance, flexibility, solderability and flowability during processing of insulated wires, insulation, uniformity of heat resistance, heat resistance, and thus insulation of multilayer insulated wires. It is suitable to construct a layer. Therefore, according to the second aspect of the present invention, an insulated wire comprising the polybutylene terephthalate resin as described above is provided.

Insulated wire according to the present invention is a conductor; 50-95 wt% of polybutylene terephthalate, 1-20 wt% of styrene-ethylene-butadiene-styrene copolymer, 1-30 wt% of polyester elastomer and 0.5-10 wt% of titanium dioxide A first coating layer of a single layer or multiple layers made of a polybutylene terephthalate resin prepared by; And a second coating layer made of polyamide.

The conductor of an insulated wire can use all the conductors for general wires, such as copper.

Commercially available general polyamide may be used as the polyamide of the insulated wire, but it is preferable that the intrinsic viscosity is 1 to 2, and more preferably, the intrinsic viscosity is 1.1 to 1.3. The polyamide coating layer may be formed in multiple layers, but is preferably a single layer in consideration of elongation and bending characteristics.

In an insulated wire, polybutylene terephthalate resin and polyamide form a plurality of layers on the conductor to coat the conductor. The modified polybutylene terephthalate resin may be formed in a single layer or multiple layers, but is most preferably formed in two layers. In the case where the polybutylene terephthalate resin coats the conductor with a single layer, in order to satisfy physical properties such as voltage resistance, heat resistance, flexibility, solderability, flowability, extrudability, uniformity of appearance, and heat resistance during insulation wire processing The thickness of the resin insulating layer should be formed thick, and if the coating layer is formed thick, not only is it difficult to apply the insulated wire to the small wire, but also it is difficult to obtain properties such as solderability and workability.

Thus, in one embodiment, two layers of insulating coating layers are formed on the conductor using the modified polybutylene terephthalate resin according to the present invention so that the coating layer is as thin as possible and sufficiently exhibits the required physical properties of the insulated wire. The third layer is preferably formed of polyamide having excellent coefficient of friction. 1 shows a cross-sectional view of a multi-layered insulated wire embodiment including the resin composition according to the present invention as described above.

As shown in Fig. 1, the conductor 1 has a first layer 2 and a second layer 3 made of the modified polybutylene terephthalate resin of the present invention, and a third coating layer 4 made of polyamide. The multilayer insulated wire 5 excellent in electrical resistance, heat resistance, and abrasion resistance coated with three layers is provided by coating the film.

Each coating layer is formed by coating the conductors by extruding the layers in separate steps by a continuous operation. This is because when the modified polybutylene terephthalate and polyamide are simultaneously coated, each component is mixed with each other to form a coating layer of one layer without distinction of layers, which does not exhibit sufficient physical properties required for the insulated wire. Insulation coating at each stage has excellent insulation properties, and the overall thickness of the coating layer is extruded to 60 ~ 160㎛ to improve the characteristics compared to the conventional winding.

The insulated wire of the present invention can be produced by a conventional extrusion coating method, there is no particular limitation on the thickness of the extrusion coating insulating layer formed. For example, when the conductor has a diameter of about 0.4 mm, it is formed of a very thin multilayer insulated wire so that the general total insulation layer has a thickness of about 100 μm (about 33 μm per layer).

Extrusion coating methods for electric wires are well known to those skilled in the art and a schematic process diagram for coating is shown in FIG. 2. Preferably, the extrusion coating is controlled using an automated system to control the cylinder temperature at 160-280 ° C., the screw rotation speed at 10-30 RPM, and the ship speed of 100-500 MPM so that eccentricity does not occur. In addition, each insulation layer is installed by cooling zones for each extrusion process to be distinguished between the layers and cooled to 100 ℃ or less to the extrusion coating.

The multi-layered insulated wire having a coating layer formed of the modified polybutylene terephthalate resin of the present invention can be used in an excellent transformer of less weight and volume than the existing transformer, the multi-layered insulated wire according to the present invention is a battery charger (VTR, printer , Digital cameras, mobile phones), printers, fax machines, computers, monitors, inverters, game machines, and other small electronics.

Hereinafter, the present invention will be described in more detail with reference to the following examples. The following examples are only for illustrating the present invention, but the scope of the present invention is not limited thereto.

Example

Example 1 and Comparative Examples 1-4

As shown in Table 1 below, by mixing and polymerizing each component to prepare a modified polybutylene terephthalate resin consisting of the composition of Example 1 and Comparative Examples 1-4.

On the other hand, as the conductors, wires (solid wires) and outer stranded wires of 0.4 mm in diameter of the heat-cooled copper wire were peeled off. The first and second insulating coating layers were formed on the conductors using the modified polybutylene terephthalate resins of Examples 1 and Comparative Examples 1-4, and a third coating layer was formed of polyamide thereon to obtain a maximum finished outer diameter. The conductor was molded and coated so as to be 0.65 mm.

The insulating coating layer of the conductor was formed using a general apparatus as shown in FIG.

The conductor is supplied to the line from a delivery drum or other device, and is preheated to pass through the crosshead of the extruder and the extrusion die, so that the first extruder 6, the second extruder 7 and the third extruder ( Each coating layer is formed while passing through 8). After passing through each extruder, after cooling in the cooling zone 11, the presence or absence of the pinhole of the coated body or the outer diameter, the eccentricity, and the like, and pulled at a constant speed in the winch capstan 12 to determine the line speed Wind the drum at 13.

At the time of extrusion coating, the cylinder temperature was extrusion coated at 260 ° C., a screw rotation speed of 30 RPM and a ship speed of 300 MPM. Thereafter, multilayer insulation wire performance evaluation was performed at room temperature (25 ° C.) and humidity (45%) as follows, and the results are shown in Table 1 below.

<Wire appearance>

The appearance of the wire was visually evaluated for the presence of flaws and dirt with the insulated wire wound on the bobbin. When there was no scratch, the surface was smooth, uniform gloss and color, did not stick, and the film was not easily peeled off even when scratched with a fingernail, it was evaluated as an excellent appearance.

<Processability>

The workability of the multilayer insulated wire was evaluated by the flowability and the extrudability of the material used for the multilayer insulated wire. The flowability was evaluated by the constant discharge amount per hour in the extruder during the extrusion process. The constant discharge amount of the extruder was evaluated as being very good at less than ± 2g, good at less than ± 5g, and good at less than ± 10g based on 100g / min. Extrudeability was evaluated by the motor load (expressed in amperes) stability of the extruder. The motor load of the extruder was evaluated based on 30RPM and 20A, and the change of amperage was very good, ± 2A or less, ± 5A or less, and ± 10A or less.

<Heat resistance>

The heat resistance of the multilayer insulated wire was evaluated after winding the multilayer insulated wire 10 times under a load of 118 MPa (12 Kg / mm 2) around a mandrel having a diameter of 6 mm and heating it at 225 ° C. for 30 minutes. Then, after unwinding the multi-layered insulated wire wound on the mandrel and visually checking for cracks, if there is no abnormality, a voltage of 3,000 V is applied for 1 minute. When there is no fault in the electrical circuit, it is considered to pass through the class. Ten tests are conducted and all ten times are considered to be very good if there are no more than nine, no more than nine times to be excellent, and no more than eight times to be considered not to pass the test.

Solderability

Take 34 specimens of approx. 15 cm in length from the same bobbin as specified in KS C 3006. 16, and approximately 40 mm at the leading end of the specimen in 50 Sn specified in KS D 6704 (solder) maintained at the temperature specified for each. After soaking for the prescribed time and immediately wiping it with a suitable cloth, it was visually examined whether solderability was uniform except for about 10 mm of the upper part of the contained part to determine whether the solderability performance.

<Insulation Characteristics>

Insulation breakdown uses two-line twisting method for 0.05mm or more. The two-line twisting method takes three specimens of about 50 cm in length from the same bobbin, folds them into two pieces, joins them together, and twists the part about 12 cm in length with an appropriate twist while applying an appropriate tensile force. Cut and apply AC voltage close to sine wave of 60Hz for 1 minute. At this time, it was very good to endure the voltage of 8Kv or more, excellent to endure the voltage of 7Kv or more, and to endure the voltage of 6Kv or more.

Composition (% by weight) Comparative example Example One 2 3 4 One Polybutylene terephthalate (A) 100 90 80 70 65 Polyester elastomer (B) - 10 10 10 20 Styrene-ethylene-butadiene-styrene copolymer (C) - - 10 20 10 Titanium Dioxide (D) - - - - 5 Sum 100 100 100 100 100 characteristic Machinability × △ ○ ○ ○ Wire appearance △ ○ ○ △ ◎ Heat resistance × △ ○ △ ◎ Wear resistance △ △ △ ○ ◎ Solderability △ △ ○ ○ ◎ Insulation properties × × △ ○ ○

◎: Very good, ○: Excellent, △: Normal, ×: Poor

As can be seen in Table 1, polybutylene terephthalate (A), polyester elastomer (B), styrene-ethylene-butadiene-styrene copolymer (C) and titanium dioxide (D) are all used In the case of Example 1, all the items showed excellent physical properties. However, when the polybutylene terephthalate is used alone or no component of any one of (A) to (D) is added as in the comparative example, the physical properties required for the insulated wire are lower than those of Example 1. Can be.

Example 2-4 and Comparative Example 5

Table 2 shows the composition and physical properties of each insulated wire. The modified polybutylene terephthalate resins of Examples 2-4 and Comparative Example 5 were prepared by mixing and modifying the components shown in Table 2.

Thereafter, the conductors were multilayered using the modified polybutylene terephthalate resins of Examples 2-4 and Comparative Example 5 as the first and second coating layers and polyamide (KOPA KM333HS from Kolon) as the third layer. An insulated wire was manufactured, and then the physical properties of the insulated wire were evaluated in the same manner as in Example 1.

Each material and the insulating film forming method used in this embodiment is the same as in Example 1.

Composition (% by weight) Example Comparative example 2 3 4 5 First and second layers Polybutylene terephthalate (A) 54 74 84 95 Polyester elastomer (B) 25 20 5 - Styrene-ethylene-butadiene-styrene copolymer (C) 20 5 10 - Titanium Dioxide (D) One One 0.5 5 Thermal Stabilizer (E) 0.5 Sum 100 100 100 100 3rd floor Polyamide 100 100 100 100 characteristic Machinability ◎ ◎ ◎ △ Wire appearance ○ ◎ ◎ ○ Heat resistance ◎ ◎ ◎ △ Wear resistance ◎ ◎ ◎ ◎ Solderability ◎ ◎ ◎ △ Insulation properties ◎ ◎ △ ○

◎: very good, ○: excellent, △: normal

As shown in Table 2, the insulated wire having a coating layer composed of a polybutylene terephthalate resin composition according to the present invention shows excellent wire appearance, heat resistance, wear resistance, solderability and insulation, It can be seen that the insulated wire having a coating layer made of the resin composition of Comparative Example 5, which does not contain B) and the styrene-ethylene-butadiene-styrene copolymer (C), has poor physical properties.

(A) polybutylene terephthalate resin, (B) polyester elastomer, (C) styrene-ethylene-butadiene-styrene used in Examples 1 to 4 and Comparative Examples 1 to 5 above, (D ) Titanium dioxide, and (E) thermal stabilizer specifications are as follows.

A) Polybutylene terephthalate: Samyang's TRIBIT 1700S

B) Polyester elastomer: Samyang's TRIEL 5400

C) Styrene-Ethylene-Butadiene-Styrene Copolymer: GTV55N from Kwangsung Plastics with hardness of 75 Shore-A and flowability of 13g / min at 230 ℃ and 10Kg load.

D) Titanium Dioxide: DuPont R106

E) Thermal stabilizer: DuPont 412S, a thioester based thermal stabilizer

The modified polybutylene terephthalate resin according to the present invention can be usefully used to prepare a multi-layered insulated wire having excellent flowability and extrusion processability and improved wire appearance, heat resistance, wear resistance, solderability and insulation properties. The insulated wire having an insulating layer made of the modified polybutylene terephthalate resin of the present invention satisfies various physical properties that can be applied to electronic products which are downsized and high performance.

Claims (9)

Poly-butylene terephthalate 50-95% by weight, 1-20% by weight of styrene-ethylene-butadiene-styrene copolymer, 1-30% by weight of polyester elastomer, and 0.5-10% by weight of titanium dioxide Butylene terephthalate resin composition.  The resin composition of Claim 1 which further contains 0.1-5 weight% of a heat stabilizer. The method of claim 1, wherein the polybutylene terephthalate has a melting temperature of 220 ~ 240 ℃, intrinsic viscosity of 0.7 ~ 1.3dl / g, the styrene-ethylene-butadiene-styrene copolymer has a hardness of 70 ~ 80 And, the polyester elastomer is a resin composition, characterized in that the block copolymer of aromatic dicarboxylic acid and lower diol or polyalkylene oxide. Conductor; Poly-butylene terephthalate 50-95% by weight, styrene-ethylene-butadiene-styrene copolymer 1-20% by weight, polyester elastomer 1-30% by weight, and titanium dioxide 0.5-10% by weight Butylene terephthalate resin coating layer; And Polyamide coating layer: Multilayer insulated wire comprising a. The multilayer insulated wire according to claim 4, wherein the polybutylene terephthalate resin coating layer further comprises 0.1-5% by weight of a heat stabilizer.  The method of claim 4, wherein the polybutylene terephthalate has a melting temperature of 220 ~ 240 ℃ and intrinsic viscosity of 0.7 ~ 1.3dl / g, the styrene-ethylene-butadiene-styrene copolymer has a hardness of 70 ~ 80, and polyester Elastomer is a resin composition, characterized in that the block copolymer of aromatic dicarboxylic acid and lower diol or polyalkylene oxide. The multilayer insulated wire according to claim 4, wherein the multilayer insulated wire comprises a single layer or two layers of polybutylene terephthalate resin coating layers. Insulated electric wire containing the polybutylene terephthalate resin composition of any one of Claims 1-3. An extrusion molded article comprising the polybutylene terephthalate resin composition according to any one of claims 1 to 3.

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