JP2007161960A - Anti-rat, abrasion-resistant and flame-retardant resin composition and anti-rat insulating electric wire for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an anti-rat, abrasion-resistant and flame-retardant resin composition useful as electric wires for automobiles. <P>SOLUTION: The anti-rat, abrasion-resistant and flame-retardant resin comprises 100 parts by mass of a base resin obtained by mixing 60-95 parts by mass of a homopolypropylene (PP) having ≥500% elongation at break and ≤0.5 g/10 minutes melt mass flow rate (MFR) (230°C at 2.16 kg) with 5-40 parts by mass of a low-density polyethylene having ≥500% elongation at break and ≤0.25 g/10 minutes MFR (190°C at 2.16 Kg), 80-120 parts by mass of a metal hydroxide treated with a silicone and ≥0.1 part by mass of a rat poison and is crosslinked by electron beam irradiation. Consequently, the anti-rat, abrasion-resistant and flame-retardant resin has excellent properties, namely, heat resistance, abrasion resistance, flame retardance and anti-rat property and proper flexibility. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an anti-wear / anti-wear flame retardant resin composition useful for, for example, an automobile electric wire and the like, and an anti-insulated electric wire using the same.

In recent years, electric wires (including cables) for automobiles have been required to have characteristics such as heat resistance, wear resistance, and flame retardancy. Conventionally, in the case of an automobile electric wire mainly using a polyethylene (PE) resin composition, several types have been proposed because of its excellent properties such as cost and flame retardancy. However, electric wires using PE resin compositions are insufficient in terms of heat resistance and wear resistance, and in recent years, electric wires for automobiles using polypropylene (PP) resin compositions have begun to be used. Yes. For example, a coating material for an automobile electric wire using a composition (propylene-ethylene block copolymer) obtained by polymerizing a PP resin as a part of a resin component has been proposed (Cited document 1).
JP 2000-86858 A

  However, the required specifications for automobile wires in recent years are strict, and the above-mentioned required specifications cannot be sufficiently satisfied with the characteristics of the coating material for automobile wires using the above-described block copolymer. Furthermore, in addition to good heat resistance, wear resistance, flame retardancy, etc., the required specifications for automobile wires require moderate flexibility in handling during wiring. In particular, as will be described later, in the case of a resin composition containing a homo PP resin component, the rigidity is high and the flexibility tends to be easily lost.

Therefore, the present inventors have conducted various tests in search of a coating material for an automobile electric wire that has good heat resistance, wear resistance, flame retardancy, and the like and has appropriate flexibility.
As a result, homopolypropylene (homo PP) resin having specific characteristics is mixed with low density polyethylene (LDPE) having specific characteristics in a specific amount range to form a base resin, which is then treated with silicone. As a flame retardant for added metal hydroxides, the above-mentioned good heat resistance can be obtained by adding an appropriate amount of flame retardant aid, antioxidant, copper damage inhibitor, etc., and crosslinking by electron beam irradiation. The inventors have found that an abrasion-resistant flame-retardant resin composition having desired characteristics and having abrasion resistance, flame retardancy, and appropriate flexibility can be obtained (Cited document 2).
Japanese Patent Application No. 2005-2486325

  On the other hand, in the case of an insulated wire for an automobile, it is used as it is or used as a wire harness, but depending on the parking mode of the automobile, there is a concern that the insulated wire may bite into the vehicle and bite the insulated wire. was there. Therefore, in addition to the above-mentioned good heat resistance, wear resistance, flame retardancy and appropriate flexibility, an appropriate amount of antifungal agent was added to obtain a resin composition having good antifungal properties. .

  The present invention has been made from such a viewpoint. Basically, a predetermined amount of a flame retardant and an antifungal agent, and further, a predetermined amount with respect to a base resin composed of a homo-PP resin and LDPE. By adding a flame retardant auxiliary, an antioxidant and a copper damage inhibitor, an anti-wear and abrasion-resistant flame retardant resin composition with excellent characteristics is provided. Cable).

  The present invention according to claim 1 is characterized by 60 to 95 parts by mass of homopolypropylene (PP) having an elongation at break of 500% or more and a melt mass flow rate (MFR) of 0.5 g / 10 min (230 ° C., 2.16 Kg) or less. 100 parts by mass of base resin mixed in the range of 5 to 40 parts by mass of low density polyethylene having a point elongation of 500% or more and MFR of 0.25 g / 10 min (190 ° C., 2.16 Kg), and silicone-treated metal hydroxide 80 It consists of ˜120 parts by mass and an antifungal agent of 0.1 parts by mass or more, and is an antibacterial and abrasion resistant flame retardant resin composition characterized by being crosslinked by electron beam irradiation.

  The present invention according to claim 2 passes the flame retardancy by a 45 ° inclined combustion test at an elongation at break of 150% or more (tensile speed: 200 mm / min) by the electron beam irradiation, and wear resistance test The anti-wear / anti-wear flame retardant resin composition according to claim 1, wherein the number of scrapes is 150 times or more.

  The present invention according to claim 3 resides in the flameproof and abrasion resistant flame retardant resin composition according to claim 1 or 2, wherein the metal hydroxide is magnesium hydroxide.

  The present invention according to claim 4 is characterized in that 5 parts by mass or less of a crosslinking aid is added to 100 parts by mass of the base resin, and the anti-wear and abrasion-resistant flame-retardant resin composition according to claim 1, 2 or 3 It is in the thing.

  The present invention according to claim 5, wherein 0.5 to 4.0 parts by mass of an antioxidant is added to 100 parts by mass of the base resin. It is in the wearable flame retardant resin composition.

  The present invention according to claim 6 is characterized by adding 0.25 to 2.0 parts by mass of a copper damage inhibitor to 100 parts by mass of the base resin.に Wear resistant flame retardant resin composition.

  The present invention according to claim 7 is a fender-insulated electric wire for automobiles, characterized in that the composition according to claim 1, 2, 3, 4, 5 or 6 is coated.

According to the present invention, according to the above-described configuration, an excellent anti-wear and wear-resistant flame retardant resin composition having appropriate heat resistance, wear resistance, flame retardancy, anti- mold properties, and the like, and an appropriate flexibility can be obtained. can get. Therefore, if this is used as a wire coating material, an excellent insulated wire, in particular, an automotive insulated insulated wire can be obtained.

  The homopolypropylene (homo PP) resin used in the present invention is a resin having higher rigidity than random PP and block PP, and the properties of those specifically used include elongation at break of 500% or more (tensile speed of 200 mm). / Min), MFR 0.5 g / 10 min (230 ° C., 2.16 Kg) or less is preferable. Examples of such commercial products of homo PP resin include E111G (trade name) manufactured by Prime Polymer Co., Ltd.

  The low density polyethylene (LDPE) used in the present invention is a soft resin as compared with the high density polyethylene (HDPE), and the properties of what is specifically used include elongation at break of 500% or more (pulling speed 200 mm / min), The thing below MFR0.25g / 10min (190 degreeC, 2.16Kg) is preferable. As a commercial item of such a homo PP resin, for example, Ube Industries, UBEC150 (trade name) and the like can be mentioned.

  The purpose of the addition of LDPE is to improve the compatibility of the base resin with a flame retardant, that is, a metal hydroxide, in addition to the expected flexibility of the base resin.

  In this invention, LDPE is mixed in the range of 5-40 mass parts with respect to 60-95 mass parts of said homo PP type-resins, and 100 mass parts of base resins are obtained. The reason for this is that when the amount of LDPE added is less than 5 parts by mass, the desired softening effect cannot be obtained, and conversely, when it exceeds 40 parts by mass, the amount of homo PP resin relatively decreases, This is because good heat resistance and wear resistance due to the desired rigidity cannot be obtained.

  Examples of the flame retardant used in the present invention include metal hydroxides, and it is particularly preferable to use a metal-treated metal hydroxide. In the case of the silicone-treated one, the amount of the metal hydroxide added can be reduced in obtaining the desired flame retardant effect as compared with the case of no silicone treatment. For this reason, it is possible to suppress adverse effects caused by the large amount of addition, for example, deterioration of mechanical properties.

  In this invention, this flame retardant is 80-120 mass parts with respect to 100 mass parts of base resins. In general, when a metal hydroxide not treated with silicone is used as a flame retardant, it is necessary to add an amount exceeding 120 parts by mass with respect to 100 parts by mass of the base resin in order to obtain desired flame retardancy. In the case of the present invention, it is possible to cope with a small addition amount due to the silicone treatment effect of the metal hydroxide. However, if it is less than 80 parts by mass, the desired flame retardancy cannot be obtained, and the lower limit addition amount is 80 parts by mass. On the other hand, as the addition amount increases, the mechanical properties and the like of the resin composition decrease, so the upper limit was set to 120 parts by mass.

  Examples of the metal hydroxide of the flame retardant include magnesium hydroxide, aluminum hydroxide, calcium hydroxide and the like, but the use of magnesium hydroxide is preferable. An example of a commercially available magnesium hydroxide treated product is Kisuma 5P (trade name, manufactured by Kyowa Chemical Co., Ltd.).

  The antifungal agent used in the present invention is not particularly limited as long as it is a material that dislikes wrinkles, and capsaicins, microencapsulated cycloheximide, mercaptan, and the like, which are active ingredients for chili pepper, can be used. And the addition amount shall be 0.1 mass part or more. However, since it is sufficient that the soot does not bite, it is not necessary to add so much. Accordingly, the upper limit is preferably about 10 parts by mass.

  In addition to the above materials, other additives can be appropriately added to the resin composition of the present invention as necessary. Examples thereof include antioxidants, copper damage inhibitors, flame retardant aids, hydrogenated rubber materials for preventing whitening, and pigments.

  In particular, it is desirable to use an antioxidant and a copper damage inhibitor in combination. The reason for this is that, when used as a wire coating, the combined addition can suppress discoloration and deterioration of the resin even at high temperatures, and as a result, improved heat resistance can be obtained. The addition amount of the antioxidant is preferably 0.5 to 4.0 parts by mass with respect to 100 parts by mass of the base resin, and the addition amount of the copper damage inhibitor is 0.25 with respect to 100 parts by mass of the base resin. -2.0 mass parts is preferable. The reason is that if the lower limit value is not obtained, a desired effect cannot be obtained, and if the upper limit value is exceeded, problems such as bloom problems and cost increase occur.

  Examples of commercially available antioxidants include Irganox 1010 (trade name, manufactured by Ciba Specialty Chemicals), which is a phenolic antioxidant. Moreover, as a commercial item of a copper damage prevention agent, CDA-1 (trade name, manufactured by Asahi Denka Kogyo Co., Ltd.), which is a triazole copper damage prevention agent, is exemplified.

  Carbon black can be used as the flame retardant aid. In addition to becoming a colorant (black) of the resin composition, this addition is presumed to have effects such as formation of char (shell), reduction of diffusion of combustible gas, heat insulation and oxygen barrier. As an addition effect of the flame retardant aid, an effect of reducing the addition amount (about 20%) with respect to the flame retardant addition of the silicone-treated metal hydroxide alone (80 to 120 parts by mass) can be obtained. It is possible to minimize the reduction of the properties, particularly the tensile elongation at break. As this flame retardant aid, it is possible to deal with ordinary commercial products such as Toka Black (trade name, manufactured by Tokai Black Co., Ltd.). And about 2-8 mass parts is preferable with respect to 100 mass parts of base resins.

  In the case of the resin composition of the present invention having such a composition, for example, when it is coated as an insulator of an insulated wire, it is crosslinked by electron beam irradiation. Although the electron beam irradiation may be performed in an atmospheric pressure, it is more preferable to perform the irradiation in a nitrogen atmosphere by taking an appropriate sealing means. And the irradiation intensity | strength is preferable to be about 0.5 Mrad, for example, when the coating thickness of an insulator is 0.2 mm. By the crosslinking by the electron beam irradiation, the composition properties can be improved. Moreover, when electron beam irradiation is performed in a nitrogen atmosphere, it becomes possible to prevent deterioration of the resin due to oxygen radicals (atmospheric oxygen and dissolved oxygen) generated by electron beam irradiation.

  In crosslinking by this electron beam irradiation, a crosslinking assistant is preferably added. Although it does not specifically limit as this crosslinking adjuvant, For example, use of a trimethylol propane trimethacrylate (TMPT) is desirable. At this time, a small amount of hydroquinone (HQ) may be used in combination. HQ has a function of suppressing the self-polymerization of TMPT by heat. Examples of commercially available TMPT include NK ester TMPT (trade name) manufactured by Shin-Nakamura Chemical Co., Ltd.

  And as addition amount of a crosslinking adjuvant, it is 5 mass parts or less with respect to 100 mass parts of base resins, Preferably it is 2-5 mass parts. If the amount is too small, the effect of promoting crosslinking cannot be obtained. Conversely, if the amount exceeds 5 parts by mass, bloom (seepage from the resin) becomes a problem. Moreover, the combined addition amount of HQ is not particularly limited, but is preferably about 25000 ppm with respect to TMPT.

<Examples and comparative examples>
The anti-wear and abrasion-resistant flame-retardant resin composition of the present invention (Examples 1 to 11) having the composition shown in Tables 1 and 2 and a resin composition lacking the conditions of the present invention (Comparative Examples 1 to 9) ) To manufacture a sample insulated insulated wire. The sample insulated wire was formed by subjecting the above composition to extrusion coating (coating outer diameter φ1.3 mm) as an insulator having a thickness of 0.2 mm on a conductor having an outer diameter φ0.9 mm, and an electron beam in a nitrogen atmosphere. Irradiation was performed. The intensity of electron beam irradiation was 0.5 Mrad. Moreover, the numerical value of the compounding material in a table | surface shows a mass part. The homo PP resin used is E111G (trade name) manufactured by Prime Polymer Co., Ltd., LDPE is UBEC 150 (trade name) manufactured by Ube Industries, Ltd., and the flame retardant is silicone hydroxide-treated metal hydroxide magnesium hydroxide. Kisuma 5P (trade name, manufactured by Kyowa Chemical Co., Ltd.), antioxidant is Irganox 1010 (trade name, manufactured by Ciba Specialty Chemicals), and copper damage inhibitor is CDA-1 (trade name, manufactured by Asahi Denka Kogyo Co., Ltd.) The crosslinking aid is NK ester TMPT (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.), which is TMPT combined with 25000 ppm of HQ.

  With respect to the insulated insulated wires of each sample thus obtained, the following physical properties were evaluated, that is, “wear resistance”, “elongation at break”, “flame resistance”, “crosslinking aid”. The presence or absence of oozing out, the presence or absence of discoloration / degradation of the resin with copper tape, the presence or absence of anti-oxidant bloom, and the presence or absence of erosion damage were performed. It was written together.

  “Abrasion resistance”, which was performed according to the blade reciprocation method of the abrasion resistance test of ISO6722. Here, the needle diameter is φ0.45 mm and the load is 720 g. Then, a repeated test was conducted, and the number of scrapes until the coating was peeled off and conduction with the conductor was 150 or more passed, and less than 150 was rejected.

  “Elongation at break”, which was determined by the tensile test (based on the tensile test of JIS-C3005) as the tensile rate of 200 mm / min and the elongation at break of the insulator and the sheath. Then, the case where the elongation at break was 150% or more was regarded as acceptable and indicated by “◯”, the case where the elongation at break was less than 150% was regarded as unacceptable, and indicated by “x”.

  “Flame retardance”, which was performed in accordance with ISO 6722 45 ° inclined combustion test. The test was performed 5 times for all the samples, and the number at the time of autolysis within 70 seconds was expressed in molecules. And it was set as pass (5/5) when it self-digested within 70 seconds by all 5 of 5, and it was set as unacceptable (0 / 5-4 / 5) at other times.

  “Presence or absence of bleeding of crosslinking aid”, which was observed visually for each sample. And when all 5 out of 5 ooze out and there was no abnormality, it was set as the pass (5/5), and when it was other than that, it was set as the rejection (1/5-4/5).

  “Presence / absence of discoloration / deterioration of resin conductor by copper tape”, in which each sample was brought into contact with the copper tape, put in a constant temperature bath (140 ° C.) in this state, and left for 625 hours. And the contact part of the flame retardant resin composition coating and the conductor was visually observed. Then, all five out of the five samples were judged as acceptable when no discoloration or deterioration occurred, indicated by “◯”, and when any one of them was discolored or deteriorated, rejected, and indicated by “x”.

  “Presence / absence of bloom of antioxidant”, which was obtained by visually observing each sample. And when all 5 out of 5 ooze out and there was no abnormality, it was set as the pass (5/5), and when it was other than that, it was set as the rejection (1/5-4/5).

  “Presence or absence of carnivorous damage” was observed by placing each sample in an incubator with 10 rabbits and leaving it for 24 hours. And when all 5 out of 5 have no food damage, it is determined to be acceptable (5/5), indicated by “◯”, and when any of them is damaged, it is determined to be unacceptable (1/5 to 4/5). Displayed as “×”.

  From the above Table 1, all the characteristics, that is, the abrasion resistance, are the insulated insulated wires (Examples 1 to 11) using the resistant and abrasion resistant flame retardant resin composition according to the present invention. Good results were obtained with respect to elongation at break, flame retardancy, presence or absence of bleeding of crosslinking aid, presence or absence of resin discoloration / degradation with copper tape, presence or absence of antioxidant bloom, and presence or absence of caries damage. I know that.

On the other hand, it can be seen from Table 2 that the insulated wires lacking the requirements of the present invention (Comparative Examples 1 to 9) have problems in any of the characteristics. In addition, when Comparative Example 1 has no LDPE addition, Comparative Example 2 has a large amount of LDPE added (50 parts by mass), Comparative Example 3 has a small amount of metal hydroxide added (60 parts by mass), Comparative Example 4 has a large amount of added metal hydroxide (150 parts by mass), Comparative Example 5 has a large amount of crosslinking aid TMPT (10 parts by mass), and Comparative Example 6 has an antioxidant and a copper damage inhibitor. Are both small (antioxidant = 0.3 parts by mass, copper damage inhibitor = 0.1 parts by mass), and Comparative Example 7 has a large amount of both antioxidants and copper damage inhibitors (antioxidant = 8 parts by mass). Part, copper damage prevention agent = 4 parts by mass) and Comparative Examples 8 to 9 are both cases where the antifungal agent is small (both 0.05 parts by mass).

Claims (7)

Elongation at break 500% or more, melt mass flow rate (MFR) 0.5 g / 10 min (230 ° C., 2.16 Kg) or less homopolypropylene (PP) 60-95 parts by mass, elongation at break 500% or more, MFR 0.25 g / 10 min (190 ° C., 2.16 Kg) or less of low-density polyethylene in an amount of 5 to 40 parts by mass, base resin 100 parts by mass, silicone-treated metal hydroxide 80 to 120 parts by mass, and antifungal agent An anti-wear and wear-resistant flame-retardant resin composition comprising 0.1 part by mass or more and crosslinked by electron beam irradiation. By the electron beam irradiation, the elongation at break is 150% or more (tensile speed: 200 mm / min), the flame resistance by the 45 ° inclined combustion test is passed, and the number of scrapes of the abrasion resistance test is 150 times or more. The flameproof and abrasion resistant flame retardant resin composition according to claim 1. The anti-wear and abrasion-resistant flame-retardant resin composition according to claim 1 or 2, wherein the metal hydroxide is magnesium hydroxide. The anti-wear and wear-resistant flame-retardant resin composition according to claim 1, 2 or 3, wherein 5 parts by mass or less of a crosslinking aid is added to 100 parts by mass of the base resin. The anti-wear and abrasion-resistant flame-retardant resin composition according to claim 1, 2, 3 or 4, wherein 0.5 to 4.0 parts by mass of an antioxidant is added to 100 parts by mass of the base resin. The anti-wear and wear-resistant flame-retardant resin composition according to claim 1, wherein 0.25 to 2.0 parts by mass of a copper damage inhibitor is added to 100 parts by mass of the base resin. object. A fender-insulated electric wire for automobiles, which is coated with the composition according to claim 1, 2, 3, 4, 5 or 6.