JP2017014420A - Resin composition and insulated wire using the same - Google Patents

Abstract

A resin composition having improved wear resistance and bending characteristics at low temperatures and an insulated wire using the same are provided.
A resin composition contains a vinyl chloride resin, a plasticizer, and a flexible resin. The resin composition has a loss elastic modulus (E ″) peak temperature measured at a vibration frequency of 1 Hz of −25 ° C. or less. The resin composition is made of a resin composition and has a thickness of 0.24 mm to 0.004. A scrape abrasion test specified in ISO 6722: 2006 was performed on a wire in which a coating layer having a cross-sectional area of 1.25 mm ² was coated with a coating layer of 40 mm using a wire having a diameter of 0.45 ± 0.01 mm. In this case, the number of round trips is 400 or more.
[Selection] Figure 1

Description

  The present invention relates to a resin composition and an insulated wire using the same. Specifically, the present invention relates to a resin composition that improves wear resistance and bending characteristics at low temperatures, and an insulated wire using the resin composition.

  Electric wires such as wire harnesses used in automobiles are bent and routed in a short path, and are also required to have bending resistance in a wide temperature range in order to cope with changes in the temperature of the vehicle body. For this reason, a material having bending resistance is also used for the insulating material covering the conductor.

  As an insulating material having such bending resistance, a PVC tape in which a film base material mainly composed of polyvinyl chloride (PVC) is formed in a tape shape has been disclosed (for example, see Patent Document 1). . And in this PVC tape, it is disclosed that the film base contains a predetermined amount of PVC resin, plasticizer, nitrile rubber and flame retardant filler.

JP 2000-198895 A

  However, since the PVC-based tape of Patent Document 1 has a large amount of plasticizer and has insufficient strength, there is a fear that the abrasion resistance required for the electric wire may not be satisfied. In addition, if the amount of nitrile rubber is too small, the flexibility at low temperatures deteriorates. Furthermore, depending on the content of acrylonitrile in the nitrile rubber, the compatibility of the nitrile rubber with polyvinyl chloride decreases, resulting in wear resistance and low temperature bending. There was a risk of sex deterioration.

  The present invention has been made in view of the problems of such conventional techniques. And the objective of this invention is providing the resin composition which improved abrasion resistance and the bending characteristic at the time of low temperature, and an insulated wire using the same.

The resin composition according to the first aspect of the present invention contains a vinyl chloride resin, a plasticizer, and a flexible resin. The resin composition has a loss elastic modulus (E ″) peak temperature measured at a vibration frequency of 1 Hz of −25 ° C. or less. The resin composition is made of a resin composition and has a thickness of 0.24 mm to 0.004. A scrape abrasion test specified in ISO 6722: 2006 was performed on a wire in which a coating layer having a cross-sectional area of 1.25 mm ² was coated with a coating layer of 40 mm using a wire having a diameter of 0.45 ± 0.01 mm. In this case, the number of round trips is 400 or more.

  The resin composition according to the second aspect of the present invention relates to the resin composition according to the first aspect, and the flexible resin is acrylonitrile-butadiene rubber having an acrylonitrile content of 20 to 35% by mass. And content of the acrylonitrile-butadiene rubber with respect to 100 mass parts of vinyl chloride resin is 5-30 mass parts, and content of the plasticizer with respect to 100 mass parts of vinyl chloride resin is 15-29 mass parts.

  The insulated wire which concerns on the 3rd aspect of this invention is equipped with the coating layer which consists of a resin composition which concerns on a 1st or 2nd aspect, and the conductor coat | covered with a coating layer.

  The resin composition of the present invention contains a vinyl chloride resin, a plasticizer, and a flexible resin, and has a peak temperature of loss elastic modulus (E ″) of −25 ° C. or less. Since it has wear resistance, it can be suitably used as an insulating material for electric wires.

It is sectional drawing which shows the insulated wire which concerns on embodiment of this invention. It is the schematic for demonstrating the apparatus which performs a low-temperature flexibility test.

  Hereinafter, a resin composition and an insulated wire according to an embodiment of the present invention will be described in detail with reference to the drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

[Resin composition]
The resin composition according to this embodiment is mainly composed of a vinyl chloride resin. Vinyl chloride resin is a material that has high heat resistance without being subjected to crosslinking treatment, is excellent in electrical insulation, is inexpensive, and can be easily processed. Further, the resin composition is added with a plasticizer in order to enhance the flexibility of the vinyl chloride resin. However, only by adding a plasticizer to the vinyl chloride resin, sufficient flexibility cannot be given to the resin composition at low temperatures, and the flexibility becomes insufficient.

  Therefore, the resin composition of this embodiment contains a flexible resin in addition to the vinyl chloride resin and the plasticizer. The flexible resin is a resin for imparting flexibility to the vinyl chloride resin like the plasticizer, and by adding this, the flexibility of the resin composition at low temperature can be improved.

  Examples of the vinyl chloride resin used in the resin composition of the present embodiment include polyvinyl chloride, chlorinated polyvinyl chloride, polyvinylidene chloride, chlorinated polyethylene, vinyl chloride-vinyl acetate copolymer, and vinyl chloride-ethylene copolymer. Polymer, vinyl chloride-propylene copolymer, vinyl chloride-styrene copolymer, vinyl chloride-isobutylene copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-styrene-maleic anhydride copolymer, vinyl chloride -Styrene-acrylonitrile copolymer, vinyl chloride-butadiene copolymer, vinyl chloride-isoprene copolymer, vinyl chloride-chlorinated propylene copolymer, vinyl chloride-vinylidene chloride-vinyl acetate copolymer, vinyl chloride-malein Acid ester copolymer, vinyl chloride-methacrylic acid ester copolymer, vinyl chloride - acrylonitrile copolymer, vinyl chloride - may be mentioned various vinyl ether copolymers. These vinyl chloride resins may be used individually by 1 type, and may be used in combination of 2 or more type. The polymerization method of the vinyl chloride resin is not particularly limited, such as bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization.

  The average degree of polymerization (weight average degree of polymerization) of the vinyl chloride resin is not particularly limited, but is preferably 500 to 5000, more preferably 1000 to 3000. When the average degree of polymerization is 500 or more, it is possible to suppress a decrease in wear resistance of the obtained resin composition. Moreover, when an average polymerization degree is 5000 or less, when extruding a resin composition, the raise of the melt viscosity at the time of extrusion molding can be suppressed, and also the deterioration of kneading | mixing and moldability can be prevented. In addition, in the resin composition of this embodiment, you may use the vinyl chloride resin in the range of the said polymerization degree 1 type or in combination of 2 or more types.

  The plasticizer used in the resin composition is not particularly limited as long as it penetrates between the molecules of the vinyl chloride resin to weaken the intermolecular force of the resin and gives the vinyl chloride resin flexibility. However, in this embodiment, it is preferable to use at least one of trimellitic acid plasticizer and pyromellitic acid plasticizer as the plasticizer. Trimellitic acid plasticizers and pyromellitic acid plasticizers are excellent in heat resistance and weather resistance, and are low in volatility, and thus are suitable for resin compositions for electric wire insulating materials.

  Examples of trimellitic acid plasticizers include trimellitic acid esters. Examples of pyromellitic acid plasticizers include pyromellitic acid esters. In the trimellitic acid ester and pyromellitic acid ester, examples of the alcohol constituting the ester by dehydration condensation include saturated aliphatic alcohols having 8 to 13 carbon atoms. These alcohols may be used individually by 1 type, and may be used in combination of 2 or more type.

  The plasticizer used in the resin composition may be a plasticizer other than trimellitic acid plasticizer and pyromellitic acid plasticizer. Examples of other plasticizers include phthalic acid plasticizers and aliphatic plasticizers.

  Examples of the phthalic acid plasticizer include phthalic acid esters. In the phthalate ester, examples of the alcohol constituting the ester by dehydration condensation include saturated aliphatic alcohols having 8 to 13 carbon atoms. Moreover, these alcohols may be used individually by 1 type, and may be used in combination of 2 or more type. More specifically, the phthalic acid plasticizer is, for example, from the group consisting of di-2-ethylhexyl phthalate, di-n-octyl phthalate, diisononyl phthalate, dinonyl phthalate, diisodecyl phthalate and ditridecyl phthalate. There may be mentioned at least one selected.

  Examples of the aliphatic plasticizer include at least one selected from the group consisting of adipic acid ester, sebacic acid ester, and azelaic acid ester. In these esters, examples of the alcohol constituting the ester by dehydration condensation include saturated aliphatic alcohols having 3 to 13 carbon atoms. Moreover, these alcohols may be used individually by 1 type, and may be used in combination of 2 or more type. More specifically, examples of the aliphatic plasticizer include at least one selected from the group consisting of dioctyl adipate, isononyl adipate, dibutyl sebacate, dioctyl sebacate, and dioctyl azelate.

  In the resin composition, the content of the plasticizer with respect to 100 parts by mass of the vinyl chloride resin is preferably 15 to 29 parts by mass. When the content of the plasticizer is within this range, it is possible to improve the flexibility at low temperatures while suppressing a decrease in wear resistance.

  The flexible resin used in the resin composition of the present embodiment is not particularly limited as long as it is a resin that improves the flexibility of the resin composition at a low temperature by adding it together with a plasticizer to the vinyl chloride resin. Examples of such a flexible resin include at least selected from the group consisting of acrylonitrile-butadiene rubber (NBR), ethylene-vinyl acetate copolymer (EVA), thermoplastic polyurethane (TPU), and polyester thermoplastic elastomer (TPEE). One can be mentioned. Among these, acrylonitrile-butadiene rubber is preferable as the flexible resin from the viewpoint of achieving both low-temperature flexibility and wear resistance.

  Here, when acrylonitrile-butadiene rubber is used as the flexible resin, the content of acrylonitrile in the acrylonitrile-butadiene rubber is preferably 20 to 35% by mass. When the content of acrylonitrile is less than 20% by mass, the content of the cyano group (—CN), which is a polar group, is small, so that the compatibility with the vinyl chloride resin, which is a polar resin, is insufficient, and wear resistance In addition, the low-temperature flexibility may be deteriorated. On the other hand, when the acrylonitrile content exceeds 35% by mass, the cyano group becomes excessive and the compatibility with the vinyl chloride resin is lowered, so that the wear resistance and the low-temperature flexibility may be deteriorated.

  In the resin composition, the content of the flexible resin with respect to 100 parts by mass of the vinyl chloride resin is preferably 5 to 30 parts by mass. Even when acrylonitrile-butadiene rubber is used as the flexible resin, the content of acrylonitrile-butadiene rubber with respect to 100 parts by mass of the vinyl chloride resin is preferably 5 to 30 parts by mass. When the content of the flexible resin is within this range, the flexibility at low temperature can be improved.

  The resin composition of this embodiment can contain various additives in addition to the above materials. Additives include stabilizers, pigments, antioxidants, extenders, metal deactivators, anti-aging agents, lubricants, fillers, reinforcing agents, UV absorbers, dyes, colorants, antistatic agents, foaming agents, etc. Is mentioned.

  Next, the manufacturing method of the resin composition of this embodiment is demonstrated. The above-mentioned resin composition is prepared by heating and kneading the above-mentioned materials, and known methods can be used for the method. For example, the resin composition can be obtained by kneading the above materials using a known kneader such as a Banbury mixer, a pressure kneader, a kneading extruder, a twin screw extruder, or a roll mill. Alternatively, the above materials may be dry blended in advance using a tumbler or the like and then kneaded using the above kneader. Thus, the resin composition of this embodiment can be obtained by heat-kneading.

  In the resin composition of this embodiment, the peak temperature of the loss elastic modulus (E ″) measured at a vibration frequency of 1 Hz is −25 ° C. or lower. That is, the loss of the resin composition using a dynamic viscoelasticity measuring apparatus. When the elastic modulus (E ″) is measured at a vibration frequency of 1 Hz, the peak temperature in the temperature-loss elastic modulus curve is −25 ° C. or lower. Since the ratio of the rubber state in the resin composition increases even in a low temperature environment as the peak temperature is low, the low temperature flexibility can be enhanced.

Furthermore, a diameter of 0.45 ± is applied to an electric wire made of the above-described resin composition and having a coating layer having a thickness of 0.24 mm to 0.40 mm covered with a conductor having a cross-sectional area of 1.25 mm ^2. When the scrape wear test specified in ISO 6722: 2006 is performed using a 0.01 mm wire, the number of reciprocations is 400 or more. Since the number of reciprocations of the scrape wear test is 400 or more, it has sufficient wear resistance, so that it can be applied to an electrical insulating material of an electric wire such as a wire harness.

Thus, the resin composition of this embodiment contains a vinyl chloride resin, a plasticizer, and a flexible resin. The resin composition has a loss elastic modulus (E ″) peak temperature measured at a vibration frequency of 1 Hz of −25 ° C. or less. The resin composition is made of a resin composition and has a thickness of 0.24 mm to 0.004. A scrape abrasion test specified in ISO 6722: 2006 was performed on a wire in which a coating layer having a cross-sectional area of 1.25 mm ² was coated with a coating layer of 40 mm using a wire having a diameter of 0.45 ± 0.01 mm. In this case, the number of reciprocations is not less than 400. Such a resin composition has excellent wear resistance in addition to flexibility at low temperatures, and thus can be suitably used as an electrical insulating material for vehicle electric wires. .

[Insulated wire]
As shown in FIG. 1, the insulated wire 1 according to this embodiment includes a coating layer 3 made of the resin composition described above and a conductor 2 covered with the coating layer 3.

  As the conductor 2, a single wire constituted by one strand may be used, or a stranded wire constituted by twisting a plurality of strands may be used. A stranded wire is also a concentric stranded wire in which one or several strands are centered and the strands are concentrically twisted around it; a collective stranded wire in which a plurality of strands are twisted together in the same direction; Any composite stranded wire in which a plurality of aggregate stranded wires are twisted concentrically can be used.

  The diameter of the conductor 2 and the diameter of each strand constituting the conductor 2 are not particularly limited. Furthermore, the material of the conductor 2 is not particularly limited, and for example, general metals, conductive fibers, and conductive polymers can be used. In particular, as the material of the conductor 2, known conductive metal materials such as copper, copper alloy, aluminum, and aluminum alloy can be used. These conductive metal materials are particularly preferable because of their good flexibility and conductivity. The surface of the conductor 2 may be plated, for example, tin plating, silver plating, or nickel plating.

  The covering layer 3 covering the outer periphery of the conductor 2 is formed of a resin composition that can ensure electrical insulation with respect to the conductor 2. Specifically, the coating layer 3 is formed of the above resin composition. As described above, the resin composition of the present embodiment contains a vinyl chloride resin, a plasticizer, and a soft resin, and the peak temperature of the loss elastic modulus (E ″) is −25 ° C. or lower. Since it is excellent not only in flexibility but also in abrasion resistance, it can be suitably used as an insulating material for electric wires.

  Next, the manufacturing method of the insulated wire 1 of this embodiment is demonstrated. The covering layer 3 of the insulated wire 1 is prepared by heating and kneading the material in the same manner as in the method for producing the resin composition described above. And the method of coat | covering the conductor 2 with the coating layer 3 can also use a well-known means. For example, the coating layer 3 can be formed by a general extrusion method. And as an extruder used by an extrusion molding method, a single screw extruder or a twin screw extruder is used, for example, and what has a screw, a breaker plate, a crosshead, a distributor, a nipple, and a die can be used.

  As a specific method for producing the insulated wire 1, first, a polyvinyl chloride resin composition of the present invention is obtained by preparing a uniform molten mixture according to a conventional method. And this resin composition is used as a resin for insulation coating of electric wires, and the resin composition solidified into a tubular shape by extrusion molding with electric wires (linear conductors formed of conductive metals such as copper wires). An insulating member that becomes an insulator and covers the electric wire is formed. By such a method, the insulated wire by which the electric wire was coat | covered with the insulating member is obtained.

  And the wire harness which concerns on this embodiment is provided with the above-mentioned insulated wire 1. FIG. As described above, the insulated wire 1 of the present embodiment has higher wear resistance and lower temperature flexibility than conventional ones, and therefore can be preferably used for a wire harness that is bent and routed in a short path. .

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to these Examples.

  First, by using a kneader, melt-kneading the following vinyl chloride resin, plasticizer, and acrylonitrile-butadiene rubber (NBR) as a flexible resin in the blending amounts shown in Tables 1 and 2, each Example and Comparison Example resin compositions were prepared.

(Vinyl chloride resin)
-Polyvinyl chloride manufactured by Kaneka Corporation Product name: Kane Vinyl (registered trademark) S1003
(Plasticizer)
・ Phthalic acid plasticizer Product made by J Plus Co., Ltd. Product name: DINP (Diisononyl phthalate)
(Flexible resin)
-NBR JSR Corporation product name: JSR N220S, Acrylonitrile (AN) content: 42% by mass
-NBR JSR Corporation product name: JSR N230S, Acrylonitrile (AN) content: 35% by mass
・ Product name: JSR N242S, Acrylonitrile (AN) content: 29% by mass, manufactured by NBR JSR Corporation
-NBR JSR Corporation product name: JSR N250S, acrylonitrile (AN) content: 20% by mass
-NBR JSR Corporation product name: JSR N260S, acrylonitrile (AN) content: 15% by mass

Next, a copper core wire having a cross-sectional area of 1.25 mm ² was prepared as a metal conductor. And the said metal conductor was extrusion-molded on about 180 degreeC temperature conditions using the extrusion coating apparatus for electric wire manufacture, and the test sample coat | covered with the resin composition of each Example and the comparative example was produced. In addition, it adjusted so that the thickness of the coating layer after a coating might be set to 0.30 mm in the case of extrusion molding.

[Evaluation]
About the resin composition of an Example and a comparative example, the peak temperature of loss elastic modulus was measured with the following method. Further, the test samples of Examples and Comparative Examples were evaluated for low-temperature flexibility and wear resistance by the following methods. The results are shown in Tables 1 and 2.

<Peak temperature of loss modulus>
First, test pieces having a length of 10 mm, a width of 2 mm, and a thickness of 1 mm were prepared using the resin compositions prepared in Examples and Comparative Examples. Next, the peak temperature of the loss elastic modulus (E ″) was determined by measuring a range of −60 ° C. to 100 ° C. of the test piece of each example using a dynamic viscoelasticity measuring apparatus. The measurement conditions for the rate were: measurement mode: tensile mode, vibration frequency: 1 Hz, temperature increase rate: 2 ° C./min.

<Low temperature flexibility>
For the test samples of Examples and Comparative Examples, a bending test generally based on IEC60227-2 was performed using the apparatus shown in FIG. However, a part of the test method defined in IEC60227-2 was changed as follows.

  In the bending test, as shown in FIG. 2, two jigs 12 having curved surfaces for attaching a weight 11 to the lower end of the test sample 10 of the example and the comparative example and applying a load to the test sample 10 to bend. The center part of the test sample 10 was clamped. At this time, the diameter R of the jig 12 was 25 mm. The weight of the weight 11 was 800 g.

  Then, a 180 ° bending test was performed on the test sample 10 under the conditions that the bending speed was 30 times / minute and the test temperature was −30 ° C., and the number of bendings when the conductor was disconnected was examined. A case where the wire was not disconnected even when the number of bendings was 350 times or more was evaluated as “◯”, and a case where the wire was disconnected when the number of bendings was less than 350 was evaluated as “x”.

<Abrasion resistance>
A wear test was performed on the test samples obtained in the above examples according to the scrape wear standard of IS06722: 2006. The conditions for the scrape wear test are as follows.
・ Wear: Needle with a diameter of 0.45 ± 0.01mm ・ Load on test sample: 7N
・ Needle type: Spring wire (glossy) material ・ Frequency: 55 ± 5 cycles / minute (1 cycle = 1 reciprocating motion)
・ Needle movement: 20 ± 1mm
・ Wear length: 15.5 ± 1 mm
Test temperature: 23 ± 1 ° C
Then, even when the number of reciprocations was 400 times or more, the case where conduction was not established between the metal conductor and the wire was evaluated as “◯”, and the case where conduction was performed when the number of reciprocations was less than 400 was evaluated as “x”.

  As shown in Table 1, it can be seen that Examples 1 to 7 according to this embodiment are excellent in low-temperature flexibility because the peak temperature of the loss modulus is −25 ° C. or lower. In addition, the scrape wear test also shows good results, and it can be seen that the wear resistance is also excellent.

  On the other hand, as shown in Table 2, it can be seen that Comparative Example 1 which does not contain a flexible resin and has a peak loss elastic modulus higher than −25 ° C. is inferior in low-temperature flexibility. Moreover, it turns out that the comparative example 2 which does not contain a soft resin, the peak temperature of a loss elastic modulus is higher than -25 degreeC, and also has an excessive plasticizer content is inferior to low-temperature flexibility and abrasion resistance. And it turns out that the comparative example 3 which does not contain a soft resin and content of a plasticizer is inferior is inferior in abrasion resistance. Further, Comparative Example 4 in which the content of acrylonitrile in the acrylonitrile-butadiene rubber, which is a flexible resin, is excessive, and Comparative Example 5 in which the content of acrylonitrile is excessive may be inferior not only in low-temperature flexibility but also in wear resistance. I understand.

  Although the present invention has been described with reference to the examples and comparative examples, the present invention is not limited to these, and various modifications can be made within the scope of the gist of the present invention.

1 Insulated wire 2 Conductor 3 Cover layer

Claims (3)

A resin composition containing a vinyl chloride resin, a plasticizer, and a flexible resin,
The resin composition has a peak temperature of loss elastic modulus (E ″) measured at a vibration frequency of 1 Hz of −25 ° C. or lower,
Made from the resin composition, and the coating layer is thick 0.24Mm～0.40Mm, against wire cross-sectional area was coated on a conductor of 1.25 mm ^2, diameter 0.45 ± 0.01 mm A resin composition characterized by having a number of reciprocations of 400 or more when a scrape wear test specified in ISO 6722: 2006 is performed using a wire of No. 6. The flexible resin is an acrylonitrile-butadiene rubber having an acrylonitrile content of 20 to 35% by mass,
The content of the acrylonitrile-butadiene rubber with respect to 100 parts by mass of the vinyl chloride resin is 5 to 30 parts by mass, and the content of the plasticizer with respect to 100 parts by mass of the vinyl chloride resin is 15 to 29 parts by mass. The resin composition according to claim 1. A coating layer comprising the resin composition according to claim 1 or 2,
A conductor coated with the coating layer;
An insulated wire comprising:

Images