KR102461768B1 - Cable having a sheath layer formed from composition for sheath of cable comprising thermoplastic polyurethane resin - Google Patents

Abstract

The present invention relates to a cable having a sheath layer formed from a composition for a cable sheath comprising a thermoplastic polyurethane resin. Specifically, the present invention has excellent mechanical properties such as excellent abrasion resistance and durability and elasticity, and even when melt viscosity is increased by adding a flame retardant to improve flame retardancy, the extrusion load is effectively lowered during extrusion to improve extrudability and productivity accordingly It relates to a cable having a sheath layer formed from a composition for a cable sheath that can be used, suppresses deterioration of the base resin and can ensure continuity of the extrusion process.

Description

Cable having a sheath layer formed from composition for sheath of cable comprising thermoplastic polyurethane resin

The present invention relates to a cable having a sheath layer formed from a composition for a cable sheath comprising a thermoplastic polyurethane resin. Specifically, the present invention has excellent mechanical properties such as excellent abrasion resistance and durability and elasticity, and even when melt viscosity is increased by adding a flame retardant to improve flame retardancy, the extrusion load is effectively lowered during extrusion to improve extrudability and productivity accordingly It relates to a cable having a sheath layer formed from a composition for a cable sheath that can be used, suppresses deterioration of the base resin and can ensure continuity and uniformity of the extrusion process.

Recently, as the spread of factory automation (FA) facilities in industrial sites is expanding, the demand for FA cables used in facilities that perform repetitive movements such as transport devices and robots is increasing. , these FA cables are required to have excellent abrasion resistance, mechanical strength such as durability, and steady reliability such as excellent elasticity and flame retardancy depending on the environment of use.

In general, thermoplastic polyurethane resins are non-crosslinked and have excellent mechanical properties such as abrasion resistance and durability, and elastic strength. As a thermoplastic resin that can produce products through the

However, the use of thermoplastic polyurethane resins has been limited in fields requiring excellent flame retardant properties, such as for FA cables, because of its weak flame retardancy and the phenomenon that sparks drip by being decomposed into low molecular substances during combustion. On the other hand, there is a method of adding a flame retardant to overcome the weak flame retardancy of the thermoplastic polyurethane resin, but this increases the melt viscosity of the thermoplastic polyurethane resin to increase the extrusion load during extrusion for manufacturing the FA cable, thereby reducing productivity. Reduce.

In addition, the thermoplastic polyurethane resin is a polymer of an ester or ether group and a polyol group, and is very vulnerable to hydrolysis. Friction with the die increases, which increases the residence time in the die, causing some thermoplastic polyurethane resins to be hydrolyzed and deteriorated, and the continuity of the extrusion process is disturbed.

Therefore, it has excellent mechanical properties and elasticity such as excellent abrasion resistance and durability, and even when melt viscosity is increased by adding a flame retardant to improve flame retardancy, it can effectively lower the extrusion load during extrusion to improve extrudability and productivity accordingly, There is an urgent need for an FA cable including a sheath layer formed from a composition for a cable sheath that can suppress deterioration of the base resin and ensure continuity of the extrusion process.

An object of the present invention is to provide a cable having a sheath layer formed from a composition for a cable sheath excellent in mechanical properties such as abrasion resistance and durability, elasticity, and flame retardancy.

In addition, the present invention provides a cable having a sheath layer formed from a composition for a cable sheath that can improve extrudability, productivity, etc. by effectively lowering the extrusion load during extrusion despite an increase in melt viscosity by adding a flame retardant to improve flame retardancy aim to do

Furthermore, the present invention provides a sheath layer formed from a composition for cable sheath that can suppress deterioration of the base resin and ensure continuity and uniformity of the extrusion process as the residence time in the extrusion die increases due to the increased extrusion load. An object of the present invention is to provide a cable having

In order to solve the above problems, the present invention,

A factory automation (FA) cable having a sheath layer formed from a composition for sheath, wherein the composition for sheath includes a thermoplastic polyurethane resin, a flame retardant and a lubricant, wherein the thermoplastic polyurethane resin is prepared by polymerization of an ester group and a polyol In this case, the lubricant is an ester-based lubricant, and when the thermoplastic polyurethane resin is prepared by polymerization of an ether group and a polyol, the lubricant is an ether-based lubricant, and the lubricant is a solubility coefficient from -5 to a solubility coefficient of the thermoplastic polyurethane resin We provide factory automation (FA) cables with a solubility factor of +5.

Here, the solubility coefficient of the thermoplastic polyurethane resin provides a factory automation (FA) cable, characterized in that 20 to 24.

In addition, the thermoplastic polyurethane resin is prepared by polymerization of an ester group and a polyol, and the lubricant is an ester-based lubricant, it provides a factory automation (FA) cable.

And, the thermoplastic polyurethane resin is prepared by polymerization of an ether group and a polyol, and the lubricant is an ether-based lubricant, it provides a factory automation (FA) cable.

On the other hand, the thermoplastic polyurethane resin provides a factory automation (FA) cable, characterized in that the Shore A hardness is 80 to 95, the melting point (Tm) is 150 to 170 ℃.

In addition, based on 100 parts by weight of the thermoplastic polyurethane resin, the content of the lubricant is 0.5 to 1.5 parts by weight, it provides a factory automation (FA) cable.

And, the flame retardant, based on 100 parts by weight of the thermoplastic polyurethane resin, 20 to 30 parts by weight of a phosphorus-based flame retardant and 20 to 30 parts by weight of a melamine-based flame retardant, it provides a factory automation (FA) cable.

Here, the phosphorus-based flame retardant is an organometallic phosphinate flame retardant, and the melamine-based flame retardant is melamine cyanurate, it provides a factory automation (FA) cable.

In addition, the composition for the sheath provides a factory automation (FA) cable, characterized in that it further comprises one or more additives selected from the group consisting of hydrolysis resistance, antioxidants and talc.

On the other hand, the thermoplastic polyurethane resin has a melting point (Tm) of 150 to 170° C., and the sheath layer has tensile strength and elongation measured according to EN 50363-10-2 of 2.8 kgf / mm 2 or more and 300% or more, respectively. , When performing a flame retardancy test on a specimen of the cable having a length of 600±25 mm according to standard IEC 60332, one end of the specimen of the cable is fixed with a support, placed vertically from the ground, and 475±5 from the lower end of the support. When a flame is applied to the lower point of mm at an angle of 45±2° for 60±2 seconds and the combustion is finished, the distance between the lower end of the support and the point where the combustion is terminated exceeds 50 mm, factory automation (FA) cable is provided.

The sheath layer of a cable having a sheath layer formed from the composition for cable sheath according to the present invention exhibits excellent effects in mechanical properties such as abrasion resistance and durability, elasticity, and flame retardancy by adding a thermoplastic polyurethane resin and a flame retardant.

In addition, the sheath layer of the cable having a sheath layer formed from the composition for cable sheath according to the present invention effectively lowers the extrusion load despite the melt viscosity increased by the addition of a flame retardant by adding a specific lubricant to improve extrudability, productivity, etc. , it exhibits an excellent effect of securing continuity and uniformity of the extrusion process while suppressing deterioration of the base resin.

1 is a graph showing extrudability and extrusion uniformity during extrusion from each composition for a cable sheath in Examples and Comparative Examples.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that it can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention. Therefore, the configuration described in the embodiment described in this specification is only the most preferred embodiment of the present invention and does not represent all of the technical idea of the present invention, so various equivalents and It should be understood that there may be variations.

The present invention relates to a cable including a sheath layer formed from a composition for a cable sheath to be described later, for example, an FA cable.

The composition for a sheath forming the sheath layer of the cable according to the present invention includes a thermoplastic polyurethane resin (TPU) as a base resin, and a flame retardant to improve flame retardancy, the melt viscosity increased by the addition of the flame retardant It may contain specific lubricants and other additives to lower the extrusion load.

As the base resin, a thermoplastic polyurethane resin (TPU) has excellent mechanical properties such as tensile strength, elongation, and abrasion resistance, and has excellent flexural properties and oil resistance. In general, in the case of a thermoplastic polyurethane resin, its properties vary depending on the composition ratio of the soft part and the hard part, and the application purpose is determined. It is formed by polymerization of a group and a polyol, and thus may be a thermoplastic polyurethane resin in which the soft part is an ester-based polyol or a thermoplastic polyurethane resin in which the soft part is an ether-based polyol.

In addition, the thermoplastic polyurethane resin has a melting point (Tm) of 150 to 170 ° C., and may have a Shore A hardness of 80 to 95, and when the Shore A hardness of the thermoplastic polyurethane resin is less than 80, the hardness required for the cable sheath layer , on the other hand, if it exceeds 95, the hardness of the cable sheath layer is excessive and the bending characteristics of the cable may be greatly reduced.

The flame retardant is a phosphorus-based flame retardant such as an organometallic phosphinate flame retardant and melamine cyanurate in consideration of the processing temperature of the thermoplastic polyurethane resin as a base resin, and to facilitate char formation in case of fire. A melamine-based flame retardant such as a flame retardant may be mixed and used, and based on 100 parts by weight of the base resin, 20 to 30 parts by weight of the phosphorus-based flame retardant and 20 to 30 parts by weight of the melamine-based flame retardant may be added.

In the composition for sheath forming the sheath layer of the cable according to the present invention, the melt viscosity is increased by the addition of the flame retardant, and accordingly, the extrusion load during extrusion is increased. As a result, the extrudability of the sheath layer and the productivity of the cable and the like, and as the residence time of the composition in the extrusion die increases due to an increase in the extrusion load, the thermoplastic polyurethane resin, which is vulnerable to hydrolysis, may be partially deteriorated.

Accordingly, the composition for a sheath forming the sheath layer of the cable according to the present invention increases the melt viscosity by the addition of the flame retardant, and as a result, in order to suppress an increase in the extrusion load during extrusion, a specific lubricant is additionally included The present inventors have completed the present invention by experimentally confirming that the effect of suppressing the increase in the extrusion load is significantly improved when a lubricant having a solubility coefficient similar to that of the thermoplastic polyurethane resin is adopted.

Predictably, when the solubility coefficient of the thermoplastic polyurethane resin and the lubricant added thereto is similar, the compatibility between them increases, so that the effect of the lubricant, that is, the effect of suppressing an increase in the extrusion load, is maximized. Specifically, the solubility coefficient of the thermoplastic polyurethane resin is about 20 to 24, and the solubility coefficient of the lubricant may be the solubility coefficient ±5 of the thermoplastic polyurethane resin, that is, about 15 to 29.

In addition, the lubricant having a solubility coefficient of ±5 of the solubility coefficient of the thermoplastic polyurethane resin may be, for example, an ester-based lubricant when the thermoplastic polyurethane resin is an ester-based polyol type formed by polymerization of an ester group and a polyol, , When the thermoplastic polyurethane resin is an ether-based polyol type formed by polymerization of an ether group and a polyol, it may be an ether-based lubricant.

Here, the amount of the lubricant may be 0.5 to 1.5 parts by weight based on 100 parts by weight of the thermoplastic polyurethane resin as the base resin. When the content of the lubricant is less than 0.5 parts by weight, the effect of suppressing the increase in the extrusion load by the lubricant is insignificant, whereas when it exceeds 1.5 parts by weight, the mechanical properties such as abrasion resistance, hardness, and strength of the cable sheath layer formed from the composition are greatly reduced can be Meanwhile, the composition for a cable sheath according to the present invention may further include an antioxidant, talc, and the like as other additives.

The composition for a sheath for forming the sheath layer of the cable according to the present invention contains the above-described thermoplastic polyurethane resin as a base resin to have excellent abrasion resistance, mechanical strength, strength, hardness, etc. The problem of having sufficient flame retardancy by including a specific flame retardant in a specific content, and increasing the melt viscosity due to the addition of the flame retardant, thereby increasing the extrusion load during extrusion, is solved by adding a specific lubricant in a specific content, and as a result, the sheath layer It is possible to secure the continuity and uniformity of the extrusion process while improving the extrudability of the cable and the productivity of the cable while suppressing the deterioration of the base resin.

[Example]

1. Preparation example

A composition for a cable sheath was prepared with the components and contents shown in Table 1 below, and a sheath specimen and a cable specimen were prepared therefrom.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Suzy 100 Flame Retardant 1 25 25 25 25 35 25 25 15 Flame Retardant 2 25 25 25 25 25 35 15 25 lubricant 1 0.5 0.5 0.5 0.5 0.5 lubricant 2 0.5 lubricant 3 0.5 Etc 4 4 4 4 4 4 4 4

- Resin: Thermoplastic polyurethane resin (Shore A hardness: 80-95; Melting point (Tm): 150-170°C)- Flame retardant 1: Phosphorus expansion flame retardant (nitrogen content: 19-23 wt%; phosphorus content: 16-20 wt%) %)- Flame retardant 2: melamine cyanurate (purity 99.5%; residual cyanic acid: 0.2 wt% or less; residual melamine: 0.3 wt% or less, average particle diameter (D ₅₀ ) 1-4 μm)

- Lubricant 1: Ester wax

- Lubricant 2: Silicone-based lubricant

- Lubricant 3: Fluorine Lubricant

- Others: hydrolysis resistance, antioxidant, talc

2. Physical property evaluation

1) Room temperature physical property evaluation

Tensile strength, tear strength, and elongation were measured for each of the sheath layer specimens of Examples and Comparative Examples at an evaluation speed of 250 mm/min according to standard EN 50363-10-2. Tensile strength should be 2.8 kgf/㎟ or more, tear strength should be 50 N/m or more, and elongation should be 300% or more.

2) Oxygen index evaluation

In accordance with the standard ASTM D2863, the limit oxygen index (LOI) was measured for each of the sheath layer specimens of Examples and Comparative Examples. The limiting oxygen index should be at least 28%.

3) Flame retardant evaluation

In accordance with the standard IEC 60332, a flame retardant test was performed on a cable specimen having a sheath layer of each of Examples and Comparative Examples and having a length of 600±25 mm, and one end of each of the cable specimens was fixed with a support and placed vertically from the ground And when the flame was applied for 60±2 seconds at an angle of 45±2° to the lower point of 475±5 mm from the lower end of the support, the distance from the lower end of the support to the point where the combustion was finished was 50 mm should exceed

4) Evaluation of extrusion characteristics

Extrudability and extrusion uniformity were evaluated by measuring the amount of extrusion for a certain period and time using a Hakke mini single extruder. The amount of extrusion per hour should be 2.8 kg/h or more, and the amount of extrusion per section should be uniform.

The physical property evaluation results are shown in Table 2 and FIG. 1 below.

Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 The tensile strength
(kgf/㎟) 4.25 4.19 4.28 4.08 4.51 4.42 3.7 3.6 Elongation (%) 368 357 342 372 284 252 432 426 Tear strength (N/m) 58 54 52 53 38 32 57 56 LOI (%) 28.5 29 28.5 29 32 28 28 24 Extrusion volume per hour
(kg/h) 3.21 3.17 1.98 2.76 2.82 2.79 3.47 3.41 Extrusion Uniformity Great error error Good Good Good Great Great flame retardant pass pass pass pass pass pass fail fail

As shown in Table 2 and FIG. 1, the composition of Example 1 according to the present invention has excellent mechanical properties such as tensile strength, elongation, and tear strength of the specimen prepared therefrom, and is also excellent in LOI and flame retardancy evaluation. , extrudability and extrusion uniformity were also confirmed to be excellent. On the other hand, the compositions of Comparative Examples 1 and 2 containing silicone lubricants, fluorine-based lubricants, etc., which are not ester lubricants, exhibited a decrease in compatibility between the lubricant and the base resin. Alternatively, it was confirmed that the extrusion uniformity was below the standard, and the composition of Comparative Example 3 that did not include a lubricant was found to have lower than the standard of extrudability evaluated by the amount of extrusion per hour, and the composition of Comparative Examples 4 and 5 in which an excessive flame retardant was added. It was confirmed that the composition had lowered mechanical properties such as elongation and tear strength and lowered extrudability, and the compositions of Comparative Examples 6 and 7 in which the flame retardant was insufficiently added had lower flame retardancy than the standard.

In the above, although the present invention has been described with reference to limited embodiments and drawings, the present invention is not limited thereto and will be described below with the technical idea of the present invention by those of ordinary skill in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalents of the claims.

Claims (10)

A factory automation (FA) cable having a sheath layer formed from a composition for a sheath, comprising:
The composition for the sheath includes a thermoplastic polyurethane resin, a flame retardant and a lubricant,
When the thermoplastic polyurethane resin is prepared by polymerization of an ester group and a polyol, the lubricant is an ester-based lubricant,
When the thermoplastic polyurethane resin is prepared by polymerization of an ether group and a polyol, the lubricant is an ether-based lubricant,
The lubricant has a solubility coefficient of -5 to solubility coefficient +5 of the thermoplastic polyurethane resin, factory automation (FA) cable. According to claim 1,
The solubility coefficient of the thermoplastic polyurethane resin is 20 to 24, characterized in that, factory automation (FA) cable. 3. The method of claim 2,
The thermoplastic polyurethane resin is prepared by polymerization of an ester group and a polyol, and the lubricant is an ester lubricant, a factory automation (FA) cable. 3. The method of claim 2,
A factory automation (FA) cable, characterized in that the thermoplastic polyurethane resin is prepared by polymerization of an ether group and a polyol, and the lubricant is an ether-based lubricant. 5. The method according to any one of claims 1 to 4,
The thermoplastic polyurethane resin has a shore A hardness of 80 to 95, and a melting point (Tm) of 150 to 170° C., characterized in that the factory automation (FA) cable. 5. The method according to any one of claims 1 to 4,
Based on 100 parts by weight of the thermoplastic polyurethane resin, the content of the lubricant is 0.5 to 1.5 parts by weight, factory automation (FA) cable. 5. The method according to any one of claims 1 to 4,
The flame retardant, based on 100 parts by weight of the thermoplastic polyurethane resin, 20 to 30 parts by weight of a phosphorus-based flame retardant and 20 to 30 parts by weight of a melamine-based flame retardant, factory automation (FA) cable. 8. The method of claim 7,
The phosphorus-based flame retardant is an organometallic phosphinate flame retardant, and the melamine-based flame retardant is melamine cyanurate, a factory automation (FA) cable. 5. The method according to any one of claims 1 to 4,
The composition for the sheath further comprises one or more additives selected from the group consisting of hydrolysis resistance, antioxidants and talc, factory automation (FA) cable. 5. The method according to any one of claims 1 to 4,
The thermoplastic polyurethane resin has a melting point (Tm) of 150 to 170 °C,
The sheath layer has a tensile strength and an elongation of 2.8 kgf/mm 2 or more and 300% or more, respectively, measured according to EN 50363-10-2,
When performing a flame retardancy test on a specimen of the cable having a length of 600±25 mm according to standard IEC 60332, one end of the specimen of the cable is fixed with a support and placed vertically from the ground, and 475±5 mm from the lower end of the support. Factory automation (FA) cable, in which the distance between the lower end of the support and the point at which the combustion is terminated exceeds 50 mm when the combustion is finished after applying a flame at an angle of 45 ± 2° to the lower point of the .

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