JP2017193640A - Thermoplastic resin composition for electric wire coating and heat-resistant electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic resin composition which has excellent flame retardancy and flexibility and has good heat resistance and gasoline resistance even without a post-crosslinking treatment, and to provide an electric wire using the thermoplastic resin composition as a coating material, especially a heat-resistant electric wire for a vehicle.SOLUTION: The thermoplastic resin composition contains (A) a thermoplastic polymer, (B) a non-aromatic rubber softener, (C) a metal hydrate, (D) an organic peroxide, (E) an antioxidant, and (F) a coupling agent, the thermoplastic polymer comprising: (a1) 5 mass% or more and less than 50 mass% of a propylene-based polymer having a melting point of 150°C or higher; (a2) 10 mass% or more and less than 60 mass% of an ethylenic polymer; (a3) 5 mass% or more and less than 50 mass% of a hydrogenated product of a block copolymer of an aromatic vinyl compound and a conjugated diene compound, or the like; and (a4) 1 mass% or more and less than 30 mass% of an unsaturated carboxylic acid-modified olefinic polymer or the like.SELECTED DRAWING: Figure 1

Description

The present invention relates to a thermoplastic resin composition and an electric wire using the same. More specifically, a thermoplastic resin composition that is excellent in flame retardancy, flexibility, heat resistance, and gasoline resistance and is suitable as a material for covering electric wires, and electric wires using the thermoplastic resin composition as a covering material, particularly heat resistance for vehicles. Regarding electric wires.

Electric wires used in vehicles, for example, high-voltage electric wires for automobiles and wires used in wiring in an engine room, since the assumed usage environment is severe, usually the rated operating temperature is 120 ° C or 150 ° C. A so-called heat-resistant electric wire having excellent heat resistance is used. From the viewpoint of adapting to the various characteristics required for vehicle wires such as heat resistance and flame retardancy, such vehicle wires have heretofore used unvulcanized rubber or ethylene copolymers as base resins. After molding an electric wire using a thermoplastic material such as a resin composition, it has been produced by further post-crosslinking treatment such as sulfur vulcanization, water crosslinking, organic peroxide crosslinking, and electron beam crosslinking. However, there has been a problem that material recycling cannot be performed by performing post-crosslinking treatment.

Therefore, as a wire coating material, a vinyl aromatic thermoplastic elastomer composition comprising a block copolymer such as a styrene / isoprene block copolymer and polypropylene as a base resin and a non-aromatic rubber softener added as a softener. Resin composition having high strength, excellent wear resistance, and flame retardancy, obtained by subjecting a product to partial cross-linking with an organic peroxide through a metal hydrate that has been surface-treated with silane Have been proposed (Patent Document 1). However, this technique does not sufficiently satisfy heat resistance such as heat deformation resistance and heat aging characteristics as a coating material for heat resistant electric wires for vehicles.

Further, as a wire coating material having good heat resistance, a resin composition containing a thermoplastic composition resin such as an ethylene polymer, a non-halogen flame retardant such as a metal hydrate, and a silane coupling agent is also known. (For example, Patent Document 2). However, this technology is not satisfactory in terms of flexibility and gasoline resistance as a covering material for heat-resistant electric wires for vehicles. Moreover, the problem that post-crosslinking treatment with hot water is necessary after coating molding and material recycling cannot be performed has not been solved.

For the problem of gasoline resistance, it has been proposed to use a silicone-based elastomer as the thermoplastic resin. However, new problems such as higher costs arise, and the problems of flexibility and recyclability are still not solved.

JP 2000-315424 A JP 2012-255077 A

An object of the present invention is to provide a thermoplastic resin composition excellent in flame retardancy and flexibility and having good heat resistance and gasoline resistance without post-crosslinking treatment, and an electric wire using this as a coating material, particularly a vehicle It is to provide a heat-resistant electric wire for use.

As a result of intensive studies, the present inventor has found that a specific thermoplastic resin composition can achieve the above-described problem.

That is, the present invention comprises (A) a thermoplastic polymer, (B) a softener for non-aromatic rubber, (C) a metal hydrate, (D) an organic peroxide, (E) an antioxidant, and (F) including a coupling agent;
The component (A) is
(A1) 5% by mass or more and less than 50% by mass of a propylene polymer having a melting point of 150 ° C. or higher;
(A2) ethylene polymer 10% by mass or more and less than 60% by mass;
(A3) Block copolymer of aromatic vinyl compound and conjugated diene compound, block copolymer of aromatic vinyl compound and isobutylene, and hydrogenated block copolymer of aromatic vinyl compound and conjugated diene compound One or more selected from the group consisting of 5% by mass or more and less than 50% by mass;
(A4) One or more types selected from the group consisting of an unsaturated carboxylic acid-modified olefin polymer, an unsaturated carboxylic acid-modified aromatic vinyl compound elastomer, and an epoxy group-containing olefin polymer 1% by mass to 30% by mass %Less than;
Where the total of the component (a1), the component (a2), the component (a3), and the component (a4) is 100% by mass; the component (E) is converted into the component (A) And a total of 100 parts by mass of the above component (B). The content is more than 1 part by mass and 15 parts by mass or less; a thermoplastic resin composition.

2nd invention makes the sum total of the said component (A) and the said component (B) 100 mass%, 70-95 mass% of said components (A); and 30-5 mass% of said components (B); The component (C) is 30 to 150 parts by mass; the component (D) is 0.01 to 1.0 part by mass with respect to a total of 100 parts by mass of the component (A) and the component (B). (E) 1-15 mass parts; and the said component (F) 0.1-8 mass parts; It is a thermoplastic resin composition as described in 1st invention.

In a third invention, the component (a2) is a copolymer of (a2-1) ethylene having a density of 860 to 935 Kg / m ³ and an α-olefin having 4 to 10 carbon atoms:
(A2-2) A thermoplastic resin composition according to the first invention or the second invention, comprising one or more selected from the group consisting of polar ethylene copolymers.

According to a fourth invention, any one of the first to third inventions, wherein the component (E) includes (E-1) a hindered phenol antioxidant; and (E-2) a thioether antioxidant. 1. The thermoplastic resin composition according to 1.

A fifth invention is an electric wire including the thermoplastic resin composition according to any one of the first to fourth inventions.

6th invention is an electric wire as described in 5th invention for vehicles.

A seventh invention is a method for producing an electric wire according to the fifth or sixth invention, wherein (1) the component (D) is melt-kneaded for 30 seconds or more at a temperature equal to or higher than the one-minute half-life temperature. And a step of obtaining the thermoplastic resin composition according to any one of the first to fourth inventions; (2) a step of forming an electric wire using the thermoplastic resin composition obtained in the step (1). And (3) a step of post-crosslinking treatment.

The thermoplastic resin composition of the present invention is excellent in flame retardancy and flexibility, and has good heat resistance and gasoline resistance even without post-crosslinking treatment. Therefore, it can be suitably used as a coating material for electric wires, particularly heat-resistant electric wires for vehicles.

1. Thermoplastic resin composition:
The thermoplastic resin composition of the present invention comprises (A) a thermoplastic polymer, (B) a softener for non-aromatic rubber, (C) a metal hydrate, (D) an organic peroxide, (E) an oxidation. An inhibitor, and (F) a coupling agent. Hereinafter, each component will be described.

(A) Thermoplastic polymer:
The component (A) is a thermoplastic polymer, and accepts the components (B) to (F) and an optional component to be used as desired, and functions to improve mechanical properties.
The component (A) is
(A1) Propylene polymer having a melting point (Tm) of 150 ° C. or higher 5% by mass or more and less than 50% by mass;
(A2) ethylene polymer 10% by mass or more and less than 60% by mass;
(A3) Block copolymer of aromatic vinyl compound and conjugated diene compound, block copolymer of aromatic vinyl compound and isobutylene, and hydrogenated block copolymer of aromatic vinyl compound and conjugated diene compound One or more selected from the group consisting of 5% by weight or more and less than 50% by weight; and
(A4) One or more types selected from the group consisting of an unsaturated carboxylic acid-modified olefin polymer, an unsaturated carboxylic acid-modified aromatic vinyl compound elastomer, and an epoxy group-containing olefin polymer 1% by mass to 30% by mass %Less than;
Consists of. Here, the sum of the component (a1), the component (a2), the component (a3), and the component (a4) is 100% by mass.

The blending ratio of the component (A) and the component (B) is usually from the viewpoint of the balance between flexibility and mechanical properties, with the total of the component (A) and the component (B) being 100% by mass. The component (A) is 70 to 95% by mass (the component (B) is 30 to 5% by mass), preferably the component (A) is 80 to 95% by mass (the component (B) is 20 to 5% by mass). .

(A1) Propylene polymer The component (a1) is a propylene polymer having a melting point of 150C or higher. The component (a1) functions to improve heat deformation resistance and gasoline resistance.

The component (a1) is not limited except that the melting point is 150 ° C. or higher, and any propylene polymer can be used. Examples of the component (a1) include propylene homopolymers, copolymers of propylene and a small amount of other α-olefins (including block copolymers and random copolymers). . As said component (a1), these 1 type, or 2 or more types of mixtures can be used.

Examples of the α-olefin include ethylene, 1-butene, 1-hexene, 1-octene, 1-decane, 3-methyl-1-pentene, and 4-methyl-1-pentene. One or more of these can be used as the α-olefin.

In this specification, melting | fusing point is based on JISK7121-1987, uses a Diamond DSC type | mold differential scanning calorimeter of PerkinElmer Japan Co., Ltd., hold | maintains at 230 degreeC for 5 minutes, -10 degreeC at 10 degreeC / min. 2nd melting curve (melting curve measured in the last heating process) measured by a program that cools to -10 ° C and holds at -10 ° C for 5 minutes and raises the temperature to 230 ° C at 10 ° C / min. The peak top melting point.

The melting point of the component (a1) is 150 ° C. or higher, preferably 160 or higher, from the viewpoint of heat deformation resistance. Although there is no particular upper limit of the melting point, since it is a propylene polymer, what is usually available is at most about 167 ° C.

The melt mass flow rate measured under the conditions of a temperature of 230 ° C. and a load of 21.18 N in accordance with JIS K 7210-1999 of the component (a1) is not particularly limited, but is usually 0.1 to 100 g from the viewpoint of moldability. / 10 minutes, preferably 0.3-30 g / 10 minutes.

The blending ratio of the component (a1) in the component (A) is such that the total of the component (a1), the component (a2), the component (a3), and the component (a4) is 100% by mass. From the viewpoint of heat deformability, it is 5% by mass or more, preferably 10% by mass or more. On the other hand, from the viewpoint of flexibility and tensile elongation, it is less than 50% by mass, preferably 35% by mass or less.

(A2) Ethylene polymer:
The component (a2) is an ethylene polymer. The component (a2) serves to improve flexibility and tensile elongation.

Examples of the component (a2) include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, a copolymer plastomer of ethylene and α-olefin, a copolymer elastomer of ethylene and α-olefin, and Examples thereof include polar ethylene polymers. As said component (a2), these 1 type, or 2 or more types of mixtures can be used.

Among these, as the component (a2), (a2-1) a density of 860 to 935 Kg / m ³ , preferably 870 to 920 Kg / m ³ , of ethylene and an α-olefin having 4 to 10 carbon atoms, Copolymers (including random copolymers and block copolymers) polymerized using a metallocene catalyst are preferred. Tensile strength, tensile elongation, and cold resistance are improved.

Examples of the α-olefin having 4 to 10 carbon atoms include 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decane. Among these, from the viewpoint of tensile strength, tensile elongation, and cold resistance, α-olefins having 6 to 8 carbon atoms are preferable, and 1-hexene, 4-methyl-1-pentene, and 1-octene are more preferable. preferable. One or more of these can be used as the α-olefin having 4 to 10 carbon atoms.

In these, as said component (a2), (a2-2) polar ethylene-type copolymer is preferable. Flame retardancy, tensile strength, and tensile elongation are improved. The component (a2-2) polar ethylene copolymer is a copolymer of ethylene and a polar group-containing monomer, and a derivative thereof.

Examples of the polar group-containing monomer include vinyl acetate; alkyl acrylates such as methyl acrylate, ethyl acrylate, and butyl acrylate; alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, and butyl methacrylate. Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, and fumaric acid; and maleic anhydride, itaconic acid monoester, itaconic acid diester, itaconic anhydride, fumaric acid monoester, fumaric acid diester, And derivatives of unsaturated carboxylic acids such as fumaric anhydride; One or more of these can be used as the polar group-containing monomer.

Examples of the component (a2-2) include ethylene / vinyl acetate copolymer (EVA), ethylene / methyl methacrylate copolymer (EMMA), ethylene / ethyl acrylate copolymer (EEA), and ethylene / acrylic. Methyl acid copolymer (EMA), ethylene / acrylic acid copolymer (EAA), ethylene / methacrylic acid copolymer (EMAA), and ethylene system in which ethylene / methacrylic acid copolymer molecules are crosslinked with metal ions Examples include ionomer resins. Among these, the component (a2-2) is preferably an ethylene / vinyl acetate copolymer (EVA) or an ethylene / ethyl acrylate copolymer (EEA) from the viewpoint of flame retardancy. As said component (a2-2), these 1 type, or 2 or more types of mixtures can be used.

The component (a2-1) and the component (a2-2) may be used alone or a mixture of both. When the total of the said component (a2-1) and the said component (a2-2) is 100 mass%, the mixture ratio of the said component (a2-2) is 50-100 mass% (the said component (a2-1) of It is preferable to use it in such an amount that the blending ratio is 50 to 0% by mass). Good balance between tensile elongation and tensile strength.

The content of the structural unit derived from ethylene in the component (a2) depends on the kind of comonomer copolymerized with ethylene and the molecular structure (whether it is linear or has a long chain branch). From the viewpoint of tensile strength, it may be preferably 50% by mass or more, more preferably 60% by mass or more. On the other hand, from the viewpoint of tensile elongation, it may be preferably 90% by mass or less, more preferably 85% by mass or less.

The melt mass flow rate measured under conditions of a temperature of 190 ° C. and a load of 21.18 N according to JIS K 7210-1999 of the component (a2) is not particularly limited, but is preferably 0.05 g / 10 from the viewpoint of moldability. Min or more, more preferably 0.1 g / 10 min or more. On the other hand, from the viewpoint of mechanical properties, it may be preferably 150 g / min or less, more preferably 30 g / 10 min or less.

The blending ratio of the component (a2) in the component (A) is flexible so that the total of the component (a1), the component (a2), the component (a3), and the component (a4) is 100% by mass. From the viewpoints of properties, tensile strength, and tensile elongation, it is 10% by mass or more, preferably 20% by mass or more. On the other hand, from the viewpoint of heat deformation resistance, it is less than 60% by mass, preferably 55% by mass or less.

(A3) Aromatic vinyl compound block copolymer and the like:
The component (a3) is composed of a block copolymer of an aromatic vinyl compound and a conjugated diene compound, a block copolymer of an aromatic vinyl compound and isobutylene, and a block copolymer of an aromatic vinyl compound and a conjugated diene compound. One or more selected from the group consisting of The component (a3) serves to improve heat deformation resistance and flexibility.

The block copolymer of the aromatic vinyl compound and the conjugated diene compound is usually one or more polymer blocks A mainly composed of an aromatic vinyl compound, preferably two or more from the viewpoint of mechanical properties. It is a block copolymer composed of one or more polymer blocks B mainly composed of a diene compound. For example, a block copolymer having a structure such as A-B, A-B-A, B-A-B-A, or A-B-A-B-A can be given.

The block copolymer of the aromatic vinyl compound and isobutylene is usually one or more polymer blocks A mainly composed of an aromatic vinyl compound, preferably two or more from the viewpoint of mechanical properties, and mainly composed of isobutylene. It is a block copolymer consisting of one or more polymer blocks B. For example, a block copolymer having a structure such as A-B, A-B-A, B-A-B-A, or A-B-A-B-A can be given.

The hydrogenated block copolymer of the aromatic vinyl compound and the conjugated diene compound is obtained by adding hydrogen to the carbon-carbon double bond in the block copolymer of the aromatic vinyl compound and the conjugated diene compound. It is a substance obtained by making carbon / carbon single bond. The hydrogenation can be performed by a known method, for example, by hydrogenation using a hydrogenation catalyst in an inert solvent.

Hydrogenation rate of hydrogenated product of block copolymer of aromatic vinyl compound and conjugated diene compound (carbon / carbon double bond in block copolymer of aromatic vinyl compound and conjugated diene compound before hydrogenation) The ratio of the number of bonds that have become carbon / carbon single bonds by hydrogenation to the number of carbon atoms is not particularly limited, but is usually 50% or more, preferably 70% or more, and more preferably 90% from the viewpoint of heat aging resistance. % Or more.

The aromatic vinyl compound is a polymerizable monomer having a polymerizable carbon / carbon double bond and an aromatic ring. Examples of the aromatic vinyl compound include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-p-aminoethylstyrene, vinyl. Examples thereof include toluene and p-tert-butylstyrene. Of these, styrene is preferred. One or more of these can be used as the aromatic vinyl compound.

The conjugated diene compound is a polymerizable monomer having a structure in which two carbon / carbon double bonds are connected by one carbon / carbon single bond. Examples of the conjugated diene compound include 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), 2,3-dimethyl-1,3-butadiene, and chloroprene (2-chloro-1,3). -Butadiene) and the like. Of these, 1,3-butadiene and isoprene are preferred. One or more of these can be used as the conjugated diene compound.

The content of the structural unit derived from the aromatic vinyl compound in the component (a3) is not particularly limited, but is preferably 5 to 50% by mass, more preferably 20 from the viewpoint of heat deformation resistance and flexibility. It may be -40 mass%.

The polymer block A is a polymer block composed only of the aromatic vinyl compound or a copolymer block of the aromatic vinyl compound and the conjugated diene compound or isobutylene. In the case where the polymer block A is the copolymer block, the content of the structural unit derived from the aromatic vinyl compound in the polymer block A is not particularly limited, but is usually from the viewpoint of heat resistance. It may be 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more. The distribution of structural units derived from the conjugated diene compound or isobutylene in the polymer block A is not particularly limited. When there are two or more polymer blocks A, they may have the same structure or different structures.

The polymer block B is a polymer block composed only of the conjugated diene compound or isobutylene, or a copolymer block of the aromatic vinyl compound and the conjugated diene compound or isobutylene. In the case where the polymer block B is the copolymer block, the content of the structural unit derived from the conjugated diene compound or isobutylene in the polymer block B is not particularly limited, but from the viewpoint of flexibility, Usually, it may be 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more. The distribution of the structural units derived from the aromatic vinyl compound in the polymer block B is not particularly limited. The bonding mode of the conjugated diene compound or isobutylene and the conjugated diene compound (hereinafter sometimes abbreviated as microstructure) is not particularly limited. When there are two or more polymer blocks B, these may have the same structure or different structures.

Examples of the block copolymer of the aromatic vinyl compound and the conjugated diene compound include styrene / butadiene / styrene block copolymer (SBS) and styrene / isoprene / styrene block copolymer (SIS). Can do. Examples of the block copolymer of the aromatic vinyl compound and isobutylene include styrene / isobutylene / styrene copolymer (SIBS). Examples of the hydrogenated block copolymer of the aromatic vinyl compound and the conjugated diene compound include styrene / ethylene / butene copolymer (SEB), styrene / ethylene / propylene copolymer (SEP), styrene / Examples thereof include an ethylene / butene / styrene copolymer (SEBS), a styrene / ethylene / propylene / styrene copolymer (SEPS), and a styrene / ethylene / ethylene / propylene / styrene copolymer (SEEPS). Among these, styrene / ethylene / butene / styrene copolymer (SEBS), styrene / ethylene / propylene / styrene copolymer (SEPS), and styrene / ethylene / ethylene / propylene / styrene copolymer (SEEPS). preferable. As said component (a3), these 1 type, or 2 or more types of mixtures can be used.

The blending ratio of the component (a3) in the component (A) is such that the total of the component (a1), the component (a2), the component (a3), and the component (a4) is 100% by mass. From the viewpoint of heat deformability, it is 5% by mass or more, preferably 15% by mass or more. On the other hand, from the viewpoint of gasoline resistance and the appearance of the molded product, it is less than 50% by mass, preferably 40% by mass or less.

(A4) Unsaturated carboxylic acid-modified olefin polymer, unsaturated carboxylic acid-modified aromatic vinyl compound elastomer, epoxy group-containing olefin polymer:
The component (a4) is at least one selected from the group consisting of an unsaturated carboxylic acid-modified olefin polymer, an unsaturated carboxylic acid-modified aromatic vinyl compound elastomer, and an epoxy group-containing olefin polymer. The component (a4) performs an important function for compatibilization of the component (A) and the component (C).

The unsaturated carboxylic acid-modified olefin polymer is a modified olefin polymer (unsaturated into an olefin polymer) using at least one selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic acid derivatives. A material obtained by graft polymerization of a saturated carboxylic acid or the like.

The olefin polymer is an α-olefin polymer or copolymer, or a copolymer of an α-olefin and a monomer copolymerizable with an α-olefin, and mainly comprises a structural unit derived from the α-olefin. (Usually 50% by mass or more, preferably 70% by mass or more, more preferably 90% by mass or more).

Examples of the α-olefin include ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decane, 3-methyl-1-pentene, and 4-methyl-1-pentene. it can. One or more of these can be used as the α-olefin.

Examples of the monomer copolymerizable with the α-olefin include vinyl acetate; alkyl acrylates such as methyl acrylate, ethyl acrylate, and butyl acrylate; methyl methacrylate, ethyl methacrylate, and butyl methacrylate. Methacrylic acid alkyl esters; unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, and fumaric acid; and maleic anhydride, itaconic acid monoester, itaconic acid diester, itaconic anhydride, fumaric acid monoester , Derivatives of unsaturated carboxylic acids such as fumaric acid diester and fumaric anhydride; 1,4-hexadiene, 5-methyl-1,5-hexadiene, 1,4-octadiene, cyclohexadiene, cyclooctadiene, dicyclopentadiene , 5-methyle 2-norbornene, 5-ethylidene-2-norbornene, 5-butylidene-2-norbornene, and nonconjugated dienes such as 5-isopropenyl-2-norbornene; and the like. One or more of these can be used as the monomer copolymerizable with the α-olefin.

Examples of the olefin polymer include linear low density polyethylene (LLDPE), low density polyethylene (LDPE), very low density polyethylene (VLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), and ethylene. .Alpha.-olefin copolymers (including random copolymers and block copolymers), polypropylene, propylene.alpha.-olefin copolymers (including random copolymers and block copolymers), polybutene, polypentene. And ethylene / vinyl acetate copolymer (EVA), ethylene / acrylic acid alkyl ester copolymer, and the like. One or more of these can be used as the olefin polymer.

Examples of the unsaturated carboxylic acid include maleic acid, itaconic acid, fumaric acid, acrylic acid, and methacrylic acid. Examples of the unsaturated carboxylic acid derivatives include maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid monoester, itaconic acid diester, itaconic anhydride, fumaric acid monoester, fumaric acid diester, fumaric anhydride, acrylic Examples thereof include alkyl acrylates such as methyl acrylate, and alkyl methacrylates such as methyl methacrylate. Among these, maleic anhydride, acrylic acid, and methacrylic acid are preferable from the viewpoint of compatibility. One or more of these can be used for modification of the olefin polymer.

In the present specification, the component (a2-2) polar ethylene copolymer (a copolymer of ethylene and a polar group-containing monomer such as an unsaturated carboxylic acid, and a derivative thereof), an unsaturated carboxylic acid, and The substance modified with one or more selected from the group consisting of unsaturated carboxylic acid derivatives is the above component (a4). In the component (a2-2), a structural unit derived from an unsaturated carboxylic acid or a derivative thereof is usually present only in the main chain. On the other hand, a substance obtained by modifying the component (a2-2) with an unsaturated carboxylic acid or the like has a significant amount of structural units derived from the unsaturated carboxylic acid or the like grafted thereon. Here, “existing only in the main chain” can be rephrased as “a structural unit derived from an unsaturated carboxylic acid or the like and grafted is not a significant amount”. In the field of resin compositions, since the significant amount of the graft amount is usually 0.1% by mass or more, “exists only in the main chain” means “a structural unit derived from an unsaturated carboxylic acid or the like”. In other words, what is grafted is usually less than 0.1% by mass, typically 0.01% by mass or less.

Among these unsaturated carboxylic acid-modified olefin polymers, from the viewpoint of compatibility, among them, maleic anhydride-modified polyethylene, maleic anhydride-modified ethylene / α-olefin copolymer, acrylic acid-modified polyethylene, acrylic acid A modified ethylene / α-olefin copolymer, a methacrylic acid-modified polyethylene, and a methacrylic acid-modified ethylene / α-olefin copolymer are preferred.

The unsaturated carboxylic acid-modified aromatic vinyl compound-based elastomer is a modified (aromatic) aromatic vinyl compound-based elastomer using at least one selected from the group consisting of unsaturated carboxylic acids and unsaturated carboxylic acid derivatives. A material obtained by graft polymerization of an unsaturated carboxylic acid or the like onto a vinyl compound elastomer.

Examples of the aromatic vinyl compound elastomer include, for example, an aromatic vinyl compound such as styrene / butadiene / styrene block copolymer (SBS) and styrene / isoprene / styrene block copolymer (SIS) and a conjugated diene compound. Block copolymer: Styrene / ethylene / butene copolymer (SEB), Styrene / ethylene / propylene copolymer (SEP), Styrene / ethylene / butene / styrene copolymer (SEBS), Styrene / ethylene / propylene / styrene Hydrogenated products of block copolymers of aromatic vinyl compounds and conjugated diene compounds such as copolymers (SEPS) and styrene / ethylene / ethylene / propylene / styrene copolymers (SEEPS); styrene / isobutylene / styrene copolymer Aromatic vinyl such as coalescence (SIBS) Block copolymer of styrene compound and isobutylene; random copolymer of aromatic vinyl compound such as styrene / butadiene random copolymer (SBR) and conjugated diene compound; and hydrogenated styrene / butadiene random copolymer ( And a hydrogenated product of a random copolymer of an aromatic vinyl compound such as HSBR) and a conjugated diene compound. One or more of these can be used as the aromatic vinyl compound elastomer.

The unsaturated carboxylic acid and the unsaturated carboxylic acid derivative have been described above. Among these, maleic anhydride, acrylic acid, and methacrylic acid are preferable from the viewpoint of compatibility. As the unsaturated carboxylic acid used for obtaining the unsaturated carboxylic acid-modified aromatic vinyl compound elastomer, one or more of these can be used.

From the viewpoint of compatibility, the unsaturated carboxylic acid-modified aromatic vinyl compound-based elastomer includes maleic anhydride-modified styrene / ethylene / butene / styrene copolymer, maleic anhydride-modified styrene / ethylene / propylene / styrene copolymer. Acrylic acid modified styrene / ethylene / butene / styrene copolymer, acrylic acid modified styrene / ethylene / propylene / styrene copolymer, methacrylic acid modified styrene / ethylene / butene / styrene copolymer, and methacrylic acid modified styrene / An ethylene / propylene / styrene copolymer is preferred.

The epoxy group-containing olefin polymer is derived from a polymerizable monomer containing an epoxy group such as glycidyl methacrylate, glycidyl acrylate, 4-hydroxybutyl methacrylate glycidyl ether, and 4-hydroxybutyl acrylate glycidyl ether, for example, glycidyl. It is an olefin polymer containing structural units such as ester, glycidyl ether, and glycidylamine.

The epoxy group-containing olefin polymer is usually modified by using one or more polymerizable monomers containing an epoxy group (graft polymerization of a polymerizable monomer containing an epoxy group on the olefin polymer). But not limited. The epoxy group-containing olefin polymer may be a copolymer of an α-olefin copolymerizable with a polymerizable monomer containing an epoxy group.

Examples of the olefin polymer used for modification by one or more polymerizable monomers containing an epoxy group include those described above as the olefin polymer used for obtaining the unsaturated carboxylic acid-modified olefin polymer. . One or more of these can be used as the olefin polymer used for modification by one or more of the polymerizable monomers containing an epoxy group.

As the component (a4), any one of an unsaturated carboxylic acid-modified olefin polymer, an unsaturated carboxylic acid-modified aromatic compound elastomer, or an epoxy group-containing olefin polymer may be used. Two or more kinds may be used in combination.

Among these, as the component (a4), an unsaturated carboxylic acid-modified olefin polymer is preferable from the viewpoints of compatibility between the component (A) and the component (C) and heat deformation resistance.

The blending ratio of the component (a4) in the component (A) is the sum of the component (a1), the component (a2), the component (a3), and the component (a4) as 100% by mass. From the viewpoint of capacity, tensile strength, and heat deformation resistance, it is 1% by mass or more, preferably 3% by mass or more. On the other hand, from the viewpoint of tensile elongation and moldability, it is less than 30% by mass, preferably 20% by mass or less.

(B) Non-aromatic rubber softener The component (B) is a non-aromatic rubber softener. The component (B) plays an important role in flexibility.

The component (B) is a non-aromatic mineral oil (hydrocarbon compound derived from petroleum or the like) or a synthetic oil (synthetic hydrocarbon compound), and is usually liquid, gel or gum at room temperature. Here, the non-aromatic system means that the mineral oil is not classified into the aromatic system in the following classification (the aromatic carbon number is less than 30%). For synthetic oils, it means that no aromatic monomer is used.

The mineral oil used as the rubber softener is a mixture of any one or more of paraffin chains, naphthene rings, and aromatic rings, and naphthenic ones having a naphthene ring carbon number of 30 to 45%. Those having an aromatic carbon number of 30% or more are referred to as aromatic, and those that do not belong to naphthenic or aromatic systems and whose paraffin chain carbon number occupies 50% or more of the total carbon number are paraffinic. It is called and distinguished.

Examples of the component (B) include paraffinic mineral oils such as linear saturated hydrocarbons, branched saturated hydrocarbons, and derivatives thereof; naphthenic mineral oils; hydrogenated polyisobutylene, polyisobutylene, and polybutene. Synthetic oils; and the like. Commercially available examples of the above component (B) include isoparaffin hydrocarbon oil “NA Solvent (trade name)” manufactured by Nippon Oil & Fats Co., Ltd., n-paraffin process oil “Diana Process Oil PW-90” (product of Idemitsu Kosan Co., Ltd.) Name) ”and“ Diana Process Oil PW-380 (trade name) ”, synthetic isoparaffinic hydrocarbon“ IP-solvent 2835 (trade name) ”from Idemitsu Petrochemical Co., Ltd., and n-paraffin-type process of Sanko Chemical Industry Co., Ltd. Oil "neothiozole (trade name)" can be listed. Among these, paraffinic mineral oil is preferable from the viewpoint of compatibility, and paraffinic mineral oil having a small number of aromatic carbon atoms is more preferable. From the viewpoint of handleability, those which are liquid at room temperature are preferred. As said component (B), these 1 type, or 2 or more types of mixtures can be used.

From the viewpoints of heat resistance and handleability, the component (B) preferably has a dynamic viscosity at 37.8 ° C. measured in accordance with JIS K2283-2000 of 20 to 1000 cSt. From the viewpoint of handleability, the pour point measured according to JIS K2269-1987 is preferably −10 to −25 ° C. Further, from the viewpoint of safety, the flash point (COC) measured according to JIS K2265-2007 is preferably 170 to 300 ° C.

The blending amount of the component (B) is preferably 5 to 30% by mass from the viewpoint of the balance between flexibility and mechanical properties, with the total of the component (A) and the component (B) being 100% by mass. Preferably it is 5-20 mass%.

(C) Metal hydrate:
The component (C) is a metal hydrate. The said component (C) has crystal water in a molecule | numerator, discharge | releases crystal water when it burns, and it functions to raise flame retardance.

Examples of the component (C) include compounds having a hydroxyl group or crystal water such as aluminum hydroxide, magnesium hydroxide, hydrated aluminum silicate, hydrated magnesium silicate, basic magnesium carbonate, and hydrotalcite. it can. The compound may be subjected to a surface treatment using any surface treatment agent such as a silane compound (silane coupling agent), a fatty acid, and a phosphate ester, and is not subjected to the surface treatment. It may be a thing. Among these, as the component (C), aluminum hydroxide and magnesium hydroxide are preferable from the viewpoint of flame retardancy. As said component (C), these 1 type, or 2 or more types of mixtures can be used.

The blending amount of the component (C) is preferably 30 parts by mass or more, more preferably 40 parts by mass, from the viewpoint of flame retardancy, with respect to a total of 100 parts by mass of the component (A) and the component (B). That's it. On the other hand, it is preferably 150 parts by mass or less, more preferably 130 parts by mass or less from the viewpoints of flexibility, mechanical properties, and heat aging resistance.

(D) Organic peroxide:
The component (D) is an organic peroxide. The component (D) functions to generate radicals during melt-kneading, cause the radicals to react in a chain manner, modify the component (A), and improve heat deformation resistance.

Examples of the organic peroxide include dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexane, 2,5-dimethyl- 2,5-di (t-butylperoxy) hexyne-3, 1,3-bis (t-butylperoxyisopropyl) benzene, 1,1-bis (t-butylperoxy) -3,3,5- Trimethylcyclohexane, n-butyl-4,4-bis (t-butylperoxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butylperoxybenzoate, t- Butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, and t-butyl kumi Such as peroxide can be mentioned. As said component (D), these 1 type, or 2 or more types of mixtures can be used.

As the component (D), 2,5-dimethyl-2,5-di- (t-butylperoxy) hexane and dicumyl parper are used from the viewpoint of odor, colorability and scorch safety of the composition. Oxides are preferred.

As a commercial item of the said component (D), "Perhexa 25B (brand name)" of Nippon Oil & Fat Co., Ltd., "Park mill D (brand name)" etc. can be mentioned, for example.

The blending amount of the component (D) is preferably 0.01 parts by mass or more, more preferably 0 with respect to 100 parts by mass of the total of the components (A) and (B) from the viewpoint of heat deformation resistance. 0.03 part by mass or more. On the other hand, from the viewpoint of tensile elongation and appearance of the molded product, it is preferably 1.0 part by mass or less, and preferably 0.5 part by mass or less.

(E) Antioxidant:
The component (E) is an antioxidant. The component (E) functions to improve heat aging resistance.

Examples of the component (E) include hindered phenol (E-1), thioether (E-2), phosphite, and amine antioxidants.

Examples of the (E-1) hindered phenol-based antioxidant include triethylene glycol-bis 3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate, 1,6-hexanediol- Bis 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,4-bis- (n-octylthio) -6-4-hydroxy-3,5-di-t-butylanilino) -1,3,5-triazine, pentaerythrityl-tetrakis 3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2,2-thio-diethylenebis-3- (3,5-di -T-butyl-4-hydroxyphenyl) propionate, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2, 2-thiobis (4-methyl-6-tert-butylphenol), N, N′-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 3,5-di-t -Butyl-4-hydroxy-benzyl phosphate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene be able to.

Examples of the (E-2) thioether-based antioxidant include pentaerythritol tetrakis (3-dodecylthiopropionate), didodecylthiodipropionate, ditridecylthiodipropionate, and ditetradecylthiodipropionate. , Dioctadecylthiodipropionate, 2-mercaptobenzimidazole, and the like.

Examples of amine-based antioxidants include polymers of 4,4′-dioctyl diphenylamine, N, N′-diphenyl-p-phenylenediamine, and 2,2,4-trimethyl-1,2-dihydroquinoline. Etc.

Examples of the phosphite antioxidant include diphenyldecyl phosphite, triphenyl phosphite, tris- (2,4-di-t-butylphenyl) phosphite, and tris- (2-ethylhexyl) phosphite. Etc.

As said component (E), these 1 type, or 2 or more types of mixtures can be used.

As said component (E), it is preferable to use together said (E-1) hindered phenolic antioxidant and said (E-2) thioether antioxidant. The heat aging resistance can be remarkably improved.

The compounding amount of the component (E) is more than 1 part by mass, preferably 3 parts by mass or more, from the viewpoint of heat aging resistance, with respect to a total of 100 parts by mass of the component (A) and the component (B). . On the other hand, the upper limit of the amount of component (E) is not particularly limited, but it is usually 15 parts by mass or less, preferably 10 parts by mass or less.

(F) Coupling agent:
The component (F) is a coupling agent. The said component (F) acts as a compatibilizer of the said component (A) and the said component (C), and there exists an effect in heat resistance.

As said component (F), a silane coupling agent, a titanate coupling agent, an acrylic acid coupling agent, etc. can be mention | raise | lifted, for example.

The silane coupling agent includes hydrolyzable groups (for example, alkoxy groups such as methoxy group and ethoxy group; acyloxy groups such as acetoxy group; halogen groups such as chloro group) and organic functional groups (for example, amino group, A silane compound having at least two different reactive groups (vinyl group, epoxy group, methacryloxy group, acryloxy group, isocyanate group, etc.).

Examples of the silane coupling agent include a vinyl silane coupling agent (a silane compound having a vinyl group and a hydrolyzable group), a methacrylic silane coupling agent (a silane compound having a methacryloxy group and a hydrolyzable group), Acrylic silane coupling agent (silane compound having acryloxy group and hydrolyzable group), epoxy silane coupling agent (silane compound having epoxy group and hydrolyzable group), amino silane coupling agent (amino group and Silane compounds having a hydrolyzable group), mercapto-based silane coupling agents (silane compounds having a mercapto group and a hydrolyzable group), and the like.

Examples of the vinyl silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (βmethoxyethoxy) silane, vinyltriacetoxysilane, vinyl-tris (n-butoxy) silane, and vinyl-tris (n -Pentoxy) silane, vinyl-tris (n-hexoxy) silane, vinyl-tris (n-heptoxy) silane, vinyl-tris (n-octoxy) silane, vinyl-tris (n-dodecyloxo) silane, vinyl-bis ( n-butoxy) methylsilane, vinyl-bis (n-pentoxy) methylsilane, vinyl-bis (n-hexoxy) methylsilane, vinyl- (n-butoxy) dimethylsilane, vinyl- (n-pentoxy) dimethylsilane, etc. Can do.

Examples of the methacrylic silane coupling agent include 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropyltriethoxysilane. Can give.

Examples of the acrylic silane coupling agent include 3-acryloxypropyltrimethoxysilane.

Examples of the epoxy silane coupling agent include 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3- Examples thereof include glycidoxypropylmethyldiethoxysilane.

Examples of the amino silane coupling agent include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (Aminoethyl) -3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N -Phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane and the like can be mentioned.

Examples of the mercapto-based silane coupling agent include 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane.

Examples of the titanate coupling agent include a monoalkoxy type having an isopropoxy group, a chelate type having an oxyacetic acid residue or an ethylene glycol residue, and a coordinated type in which a phosphite is added to a tetraalkyl titanate. Can give.

Examples of the monoalkoxy-type titanate coupling agent include isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tri (dioctyl phosphate) titanate, isopropyl tris (dioctyl pyrophosphate) titanate, and isopropyl tri (N -Aminoethyl-aminoethyl) titanate and the like.

Examples of the chelate-type titanate coupling agent include bis (dioctylpyrophosphate) oxyacetate titanate and bis (dioctylpyrophosphate) ethylene titanate.

Examples of the coordinated titanate coupling agent include tetraoctyl bis (ditridecyl phosphite) titanate and tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate. be able to.

One or more of these can be used as the component (F). Among these, the component (F) is preferably a silane coupling agent from the viewpoint of heat deformation resistance, and from the viewpoint of heat deformation resistance, a vinyl silane coupling agent and a methacrylic silane coupling agent. Is more preferable.

The compounding amount of the component (F) is a function as a compatibilizer of the component (A) and the component (C) with respect to a total of 100 parts by mass of the component (A) and the component (B). From the viewpoint of sufficiently exhibiting the above, and from the viewpoint of heat deformation resistance, it is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more. On the other hand, from the viewpoint of moldability, it may be preferably 8 parts by mass or less, and preferably 5 parts by mass or less.

The thermoplastic resin composition of the present invention is preferably (A) a thermoplastic polymer, (B) a softener for non-aromatic rubber, (C) a metal hydrate, (D) an organic peroxide, (E ) An antioxidant and (F) a coupling agent; and no silanol condensation catalyst.

Here, “not containing a silanol condensation catalyst” means “a silanol condensation catalyst is not intentionally blended” or “a silanol condensation catalyst in an amount useful for post-crosslinking treatment with hot water, so-called water crosslinking treatment”. Does not contain ". Since the compounding amount of the silanol condensation catalyst useful for performing the water crosslinking treatment is usually 0.1 parts by mass or more with respect to 100 parts by mass in total of the component (A) and the component (B). “The silanol condensation catalyst is not included” means that “the content of the silanol condensation catalyst is usually less than 0.1 parts by mass, typically 100 parts by mass of the component (A) and the component (B). In other words, it is “0.01 parts by mass or less”.

Examples of the silanol condensation catalyst include dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dioleate, stannous acetate, lead naphthenate, cobalt naphthenate, zinc caprylate, iron 2-ethylhexanoate, titanate, titanium Examples include acid tetrabutyl ester, titanate tetranonyl ester, bis (acetylacetonitrile) di-isopropyltitanium-ethylamine complex, hexylamine complex, dibutylamine complex, and pyridine complex.

In the thermoplastic resin composition of the present invention, a heat stabilizer, a light stabilizer, a metal scavenger, an ultraviolet absorber, a crystal nucleating agent, an antiblocking agent, and a sealing property are included as long as they do not contradict the purpose of the present invention. Improvers, mold release agents (eg, stearic acid, calcium stearate and silicone oil), lubricants such as polyethylene wax, colorants, pigments, inorganic fillers (eg, alumina, talc, calcium carbonate, mica, wollastonite, And clay), foaming agents (including organic and inorganic), crosslinking aids, flame retardants other than metal hydrates, and the like.

When the thermoplastic resin composition of the present invention is used as a material for directly covering a conductor, it is preferable to further include a metal scavenger. Examples of the metal scavenger include dodecanedioic acid bis [N2- (2-hydroxybenzoyl) hydrazide] and N, N′-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl). ) Propionyl] hydrazine and the like.

The thermoplastic resin composition of the present invention uses any melt kneader, and the components (A) to (F), and optional components used as desired, simultaneously or in any order in the melt kneader. It can be obtained by charging and melt-kneading.

From the viewpoint of ensuring that the component (D) works reliably, the melt kneading is preferably performed for 30 seconds or more at a temperature equal to or higher than the 1 minute half-life temperature of the component (D). More preferably, it is carried out for 1 minute or more at a temperature not lower than the half-life temperature.

Examples of the melt kneader include batch kneaders such as a pressure kneader and a mixer; extrusion kneaders such as a single screw extruder, a co-rotating twin screw extruder, and a different direction rotating twin screw extruder; a calendar roll kneader; Can give. These may be used in any combination.

The obtained composition can be formed into an arbitrary article by an arbitrary method after being pelletized by an arbitrary method. The pelletization can be performed by methods such as hot cut, strand cut, and underwater cut.

2. Electrical wire:
The electric wire of the present invention is an electric wire containing the thermoplastic resin composition of the present invention. The electric wire of the present invention is preferably an electric wire used for a high-voltage electric wire of an automobile, wiring in an engine room or the like, and as an insulating coating material or sheath material in which the thermoplastic resin composition of the present invention directly covers a conductor. It is an electric wire used.

The method for producing the electric wire of the present invention is not particularly limited. Examples of the method include (1) a step of melt kneading for 30 seconds or more at a temperature equal to or higher than the one-minute half-life temperature of the component (D) to obtain the thermoplastic resin composition of the present invention; And (3) a step of forming an electric wire using the thermoplastic resin composition obtained in (1) and (3) a step of post-crosslinking treatment.

The method for obtaining the thermoplastic resin composition of the present invention in the step (1) has been described above.

In the step (2), the method for molding the electric wire using the thermoplastic resin composition of the present invention is not particularly limited. As the above-mentioned method, for example, a cable forming apparatus equipped with an arbitrary extruder and an arbitrary die is used, and the thermoplastic resin composition of the present invention is twisted with an arbitrary conductor or several insulating coated conductors. The surroundings can be melted and extruded for coating.

Examples of the post-crosslinking treatment in the step (3) include sulfur vulcanization, water crosslinking, organic peroxide crosslinking, and electron beam crosslinking.

In the case of water crosslinking, the meaning of “not including the step of post-crosslinking treatment” will be described. In the case of water crosslinking, “does not include a step of post-crosslinking treatment” means “uses a blend of a silanol condensation catalyst in an amount useful for water crosslinking as the thermoplastic resin composition, usually at a temperature of 50 to 90 ° C. It does not include a step of immersing in warm water for 5 to 48 hours. There is no intention to exclude all the steps using water, for example, the step of melt-extruding a thermoplastic resin composition around a conductor or the like and then using water to cool at most several minutes to solidify the coating material. . The same applies to other post-crosslinking treatments.

EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

Measuring method (1) Hardness:
Based on JIS K 7215-1986, a 6 mm thick press sheet was used as a test piece, and a durometer hardness (type A) value of 15 seconds was measured. The hardness may be preferably 95 or less, more preferably 60 to 90. The 6 mm thick press sheet was prepared by hot pressing under the condition of preheating at a preheating temperature of 220 ° C. for 2 minutes and then pressing at a temperature of 220 ° C. for 2 minutes.

(2) Tensile test:
Based on JIS K7127: 1999, it measured on conditions with a tensile speed of 200 mm / min. A test piece type 5 (Fig. Of the above standard) was punched from a 1 mm thick extruded tape under the condition of a die outlet temperature of 210 ° C. using a φ20 mm extruder and an apparatus equipped with a 1 mm thick flat die. 2) was used. The tensile strength may be preferably 10.3 MPa or more, more preferably 12 MPa or more. The tensile elongation may be preferably 150% or more, more preferably 250% or more.

(3) Heat aging resistance:
A test piece obtained in the same manner as in the above (2) tensile test was treated for a certain time in a 190 ° C. gear oven, and then the tensile elongation was measured in the same manner as in the above (2) tensile test. The results were plotted with the treatment time on the horizontal axis and the tensile elongation on the vertical axis, and the treatment time at which the tensile elongation was 100% was interpolated. The heat aging resistance may be preferably 180 hours or longer, more preferably 200 hours or longer. A test piece is prepared for each processing time.

(4) Copper damage resistance:
Two rectangular sheets with a length of 16 cm and a width of 4 cm were taken from a 1 mm-thick pressed sheet, and a bare copper tape with a thickness of 0.1 mm, a length of 16 cm, and a width of 3 cm was sandwiched between the sheets, preheated at a temperature of 220 ° C. A test piece was prepared by hot pressing under conditions of a time of 2 minutes and a pressing time of 2 minutes. The 1 mm-thick press sheet was prepared by hot pressing under the condition of preheating at a preheating temperature of 220 ° C. for 2 minutes and then pressing at a temperature of 220 ° C. for 2 minutes. Whether the test piece obtained above is treated in a gear oven at 175 ° C. for a certain period of time and then bent by hand while pressing against the apex angle 20 ° of the triangular prism, whether or not the test piece is cracked outside The visual observation was repeated, and the time (day) until the test piece was cracked was determined. The copper damage resistance resistance may be preferably 8 days or longer, more preferably 20 days or longer. A test piece is prepared for each processing time.

(5) Heat deformation resistance:
In accordance with JIS C 3005-2014, a test piece with a width of 15 mm and a length of 30 mm punched from an extruded tape obtained in the same manner as in the above (2) tensile test was used, and heat deformation was performed at a temperature of 150 ° C. and a load of 1 kg. The rate was measured. The heat deformation rate may be preferably 25% or less, more preferably 20% or less.

(6) Flame retardancy:
From a 1 mm thick press sheet, a strip with a width of 6.5 mm and a length of 150 mm is punched out, and this is fixed to a steel wire (made of brass, 2 mm diameter) using a wire with a diameter of 0.1 mm. (FIG. 1). 4.26 Flame retardant of JIS C 3005: 2014, a) Horizontal flame retardant test with reference to the horizontal test, in contact with the center of the surface opposite to the side with the strip steel wire Went. The following criteria were used for evaluation. The 1 mm thick press sheet was prepared by pre-heating for 2 minutes at a pre-heating temperature of 220 ° C. and then hot pressing under a condition of applying pressure at a temperature of 220 ° C. for 2 minutes.
A: The sample does not flaming.
◯: The sample extinguishes within 60 seconds after the sample flames.
X: Continues to burn for 60 seconds or more after flame.

(7) Gasoline resistance:
The volume change rate after dipping a donut-shaped test piece having an outer diameter of 22 mm and an inner diameter of 8 mm punched from a 1 mm thick press sheet in gasoline at a temperature of 23 ° C. was measured for 20 hours. The volume change rate as gasoline resistance is preferably 30% or less, more preferably 20% or less. The conditions for producing the 1 mm-thick press sheet are the same as in (6) Flame retardancy test.

Raw material used (a1) Propylene polymer having a melting point of 150 ° C. or higher:
(A1-1) Propylene / ethylene block copolymer “VB170A (trade name)” of Sun Allomer Co., Ltd., melting point 165 ° C., melt mass flow rate 0.5 g / 10 min.
(A1-2) Propylene and ethylene block copolymer “EC9 (trade name)” of Nippon Polypro Co., Ltd., melting point 161 ° C., melt mass flow rate 0.5 g / 10 min.

(A1 ′) Reference propylene polymer:
(A1′-1) Random copolymer “PB222A (trade name)” of propylene and ethylene of Sun Allomer Co., Ltd., melting point 146 ° C., melt mass flow rate 0.8 g / 10 min.

(A2) Ethylene polymer:
(A2-1-1) Low density polyethylene “KS240T (trade name)” polymerized using a metallocene catalyst of Nippon Polyethylene Co., Ltd., density 880 Kg / m ³ , melt mass flow rate 2.2 g / 10 min, ethylene Content of structural unit derived from 77% by mass.
(A2-2-1) Ethylene / vinyl acetate copolymer “VF120T (trade name)” from Ube Maruzen Polyethylene Co., Ltd., density 940 Kg / m ³ , melt mass flow rate 1.0 g / 10 min, structural unit derived from ethylene Content of 80% by mass.

(A3) Hydrogenated block copolymer of aromatic vinyl compound and conjugated diene compound:
(A3-1) Kuraray Co., Ltd. styrene / ethylene / ethylene / propylene / styrene copolymer (SEEPS) “Septon 4077 (trade name)”, content of structural unit derived from styrene of 30% by mass.
(A3-2) Asahi Kasei Chemicals Co., Ltd. styrene / ethylene / butene / styrene copolymer (SEBS) “Tuftec N504 (trade name)”, content of structural unit derived from styrene of 30% by mass.

(A4) Unsaturated carboxylic acid-modified olefin polymer and the like:
(A4-1) Maleic anhydride-modified ethylene / α-olefin copolymer “Admer XE070 (trade name)” manufactured by Mitsui Chemicals, Inc., density 893 Kg / m ³ , melt mass flow rate 3.0 g / 10 min (190 ° C., 21.18N).
(A4-2) Maleic anhydride-modified styrene / ethylene / butene / styrene copolymer “Tuftec M1913 (trade name)” manufactured by Asahi Kasei Chemicals Corporation.
(D-3-1) Ethylene / glycidyl methacrylate copolymer “bond first BF-E (trade name) by Sumitomo Chemical Co., Ltd., melt mass flow rate 3.0 g / 10 min (190 ° C., 21.18 N).

(B) Non-aromatic rubber softener:
(B-1) Paraffin oil “Diana Process Oil PW-90 (trade name)” of Idemitsu Kosan Co., Ltd., paraffin component 71 mass%, naphthene component 29 mass%.

(C) Metal hydrate:
(C-1) Albemarle Japan Co., Ltd. surface untreated synthetic magnesium hydroxide “Magnifine H-7 (trade name)”.

(D) Organic peroxide:
(D-1) 2,5-dimethyl-2,5-di (t-butylperoxy) hexane “Perhexa 25B (trade name)” manufactured by NOF Corporation, 1 minute half-life temperature of 179 ° C.

(E) Antioxidant:
(E-1-1) A hindered phenol antioxidant from BASF, pentaerythrityl-tetrakis 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate “IRGANOX 1010 (trade name)”.
(E-2-1) A thioether-based antioxidant from Cypro Kasei Co., Ltd., pentaerythritol tetrakis (3-dodecylthiopropionate) “SEENOX 412S (trade name)”.

(F) Coupling agent:
(F-1) Silane coupling agent of Dow Corning, 3-methacryloxypropyltrimethoxysilane “OFS-6030 (trade name)”.

(G) Metal scavenger:
(G-1) ADEKA Corporation dodecanedioic acid bis [N2- (2-hydroxybenzoyl) hydrazide] “Adekastab CDA-6 (trade name)”.
(G-2) N, N′-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine “ADEKA STAB CDA-10 (trade name)” from ADEKA Corporation.

Examples 1-42
A thermoplastic resin composition was produced by melt-kneading the resin composition (part by mass) shown in any one of Tables 1 to 6 under the condition of a die outlet resin temperature of 230 ° C. using a twin screw extruder. . The above tests (1) to (7) were performed. The results are shown in any one of Tables 1-6.

The thermoplastic resin composition of the present invention is excellent in flame retardancy and flexibility, and without undergoing post-crosslinking treatment with hot water, tensile strength, tensile elongation, heat aging resistance, heat deformation resistance, and gasoline resistance Is good. It also has excellent resistance to copper damage. Therefore, it can be suitably used as a coating material for electric wires, particularly heat-resistant electric wires for vehicles.

It is a conceptual diagram of a section shape showing an example of a heat-resistant electric wire for vehicles of the present invention. This is a test piece for a flame retardancy test.

1: Insulation coating made of the thermoplastic resin composition of the present invention 2: Seven-stranded conductor

Claims (7)

(A) thermoplastic polymer, (B) softener for non-aromatic rubber, (C) metal hydrate, (D) organic peroxide, (E) antioxidant, and (F) coupling agent Including:
The component (A) is
(A1) 5% by mass or more and less than 50% by mass of a propylene polymer having a melting point of 150 ° C. or higher;
(A2) ethylene polymer 10% by mass or more and less than 60% by mass;
(A3) Block copolymer of aromatic vinyl compound and conjugated diene compound, block copolymer of aromatic vinyl compound and isobutylene, and hydrogenated block copolymer of aromatic vinyl compound and conjugated diene compound One or more selected from the group consisting of 5% by mass or more and less than 50% by mass;
(A4) One or more types selected from the group consisting of an unsaturated carboxylic acid-modified olefin polymer, an unsaturated carboxylic acid-modified aromatic vinyl compound elastomer, and an epoxy group-containing olefin polymer 1% by mass to 30% by mass %Less than;
Consists of;
Here, the sum of the component (a1), the component (a2), the component (a3), and the component (a4) is 100% by mass;
The component (E) is included in an amount of more than 1 part by mass and 15 parts by mass or less with respect to 100 parts by mass in total of the component (A) and the component (B);
Thermoplastic resin composition.
The total of the component (A) and the component (B) is 100% by mass,
The component (A) 70-95% by mass; and the component (B) 30-5% by mass;
For a total of 100 parts by mass of the component (A) and the component (B),
30 to 150 parts by mass of the component (C);
0.01 to 1.0 part by mass of the component (D);
1 to 15 parts by mass of the component (E); and
0.1-8 parts by mass of the above component (F);
The thermoplastic resin composition according to claim 1, comprising:
The component (a2) is
(A2-1) a copolymer of ethylene having a density of 860 to 935 Kg / m ³ and an α-olefin having 4 to 10 carbon atoms:
(A2-2) a polar ethylene copolymer;
The thermoplastic resin composition according to claim 1 or 2, comprising one or more selected from the group consisting of:
The component (E) is
(E-1) a hindered phenolic antioxidant; and
(E-2) a thioether-based antioxidant;
The thermoplastic resin composition according to claim 1, comprising:
The electric wire containing the thermoplastic resin composition of any one of Claims 1-4.
The electric wire according to claim 5, which is for a vehicle.
A method for producing an electric wire according to claim 5 or claim 6,
(1) A step of obtaining the thermoplastic resin composition according to any one of claims 1 to 4 by melt-kneading for 30 seconds or more at a temperature equal to or higher than the one-minute half-life temperature of the component (D);
(2) A step of forming an electric wire using the thermoplastic resin composition obtained in the step (1);
And (3) a post-crosslinking process;
Does not include the method.