JP2010150435A - Conductive composition and conductive film - Google Patents

Abstract

The present invention provides a conductive composition that can stably form a film by extrusion molding or the like and can provide a conductive film having both high toughness and high conductivity.
SOLUTION: (I) 1 to 99 parts by mass of a polyolefin resin, (b) 99 to 1 part by mass of a hydrogenated thermoplastic elastomer (provided that (I) + (B) = 100 parts by mass), and (C) A conductive composition containing 1 to 100 parts by mass of a conductive filler and having a volume resistivity of 10 ³ Ω · cm or less. (B) Suitable examples of hydrogenated thermoplastic elastomers are mainly composed of at least two polymer blocks (A) mainly composed of structural units derived from aromatic vinyl compounds and structural units derived from conjugated diene compounds. And a hydrogenated block copolymer obtained by hydrogenating a block copolymer containing at least one polymer block (B).
[Selection figure] None

Description

  The present invention relates to a conductive composition and a conductive film made of the conductive composition.

Conductive films are used in various fields such as electronic parts.
This conductive film is generally formed by dispersing conductive particles such as carbon particles and metal particles in a polymer or the like. For example, (i) a thermoplastic elastomer and 100 parts by weight of the thermoplastic elastomer. In contrast, (ii) a conductive elastomer film containing 5 to 100 parts by weight of a conductive filler and having a volume resistance value in the direction perpendicular to the film surface of 0.1 to 5 Ω · cm has been proposed. (Patent Document 1).
WO98 / 40435 publication

According to the technique described in Patent Document 1, a film having excellent conductivity can be obtained. However, since the technique described in Patent Document 1 is formed using a liquid material, it is suitable for film forming by a casting method or the like, and for forming by an extrusion forming machine such as a T-die forming machine. There is a problem that it is not suitable. If a film can be stably formed even by extrusion, it is advantageous that a film can be produced with high productivity.
On the other hand, a material comprising a polyolefin-based resin such as polypropylene and a conductive filler can be extruded, but has a problem that its use in electronic parts and the like is narrowly limited because of low toughness. In particular, when the blending ratio of the conductive filler is increased to obtain high conductivity, the toughness is lowered.
Therefore, the present invention provides a conductive composition that can stably form a film by extrusion molding or the like, and can provide a conductive film having both high toughness and high conductivity, and a conductive film. For the purpose.

  As a result of intensive studies to solve the above-mentioned problems, the present inventor has achieved the above object of the present invention according to a composition containing a polyolefin resin, a hydrogenated thermoplastic elastomer, and a conductive filler in a specific ratio. We have found that this can be achieved and completed the present invention.

That is, the present invention provides the following [1] to [4].
[1] (I) 1 to 99 parts by mass of a polyolefin-based resin, (b) 99 to 1 part by mass of a hydrogenated thermoplastic elastomer (provided that (I) + (B) = 100 parts by mass), and ( C) A conductive composition comprising 1 to 100 parts by mass of a conductive filler and having a volume resistivity of 10 ³ Ω · cm or less.
[2] The component (b) is mainly composed of at least two polymer blocks (A) mainly composed of structural units derived from an aromatic vinyl compound and at least 1 composed of structural units derived from a conjugated diene compound. A hydrogenated block copolymer obtained by hydrogenating a block copolymer containing two polymer blocks (B),
(1) The mass ratio ((A) / (B)) between the at least two polymer blocks (A) and the at least one polymer block (B) is 5/95 to 45/55,
(2) In each of the at least one polymer block (B), the content of the structural unit derived from the aromatic vinyl compound is 0 to 45% by mass, and the content of the structural unit derived from the conjugated diene compound is 55 to 55%. 100% by mass,
(3) The vinyl bond content in the whole of the at least one polymer block (B) is 60% or more,
(4) The weight average molecular weight in terms of polystyrene of the component (b) is 5 to 500,000,
(5) The hydrogenation rate of the component (b) is 80% or more,
(6) The melt flow rate measured under the conditions of 230 ° C. and 21.2 N load of the component (b) is 1 to 100 g / 10 min.
The conductive composition according to the above [1], which satisfies all of the above conditions.
[3] The conductive composition according to [1] or [2], wherein the component (c) is conductive carbon black or carbon fiber.
[4] A conductive film comprising the conductive composition according to any one of [1] to [3].

  The conductive film made of the conductive composition of the present invention can be stably formed by extrusion or the like, and has high toughness and high conductivity.

The conductive composition of the present invention contains the components (A) to (C) as essential components and other optional components as necessary.
Hereinafter, each component will be described.
[(I) component]
The component (a) used in the conductive composition of the present invention is a polyolefin resin.
Examples of polyolefin resins include α-olefin homopolymers such as ethylene, propylene, butene-1, 3-methylbutene-1, 3-methylpentene-1, 4-methylpentene-1, and copolymers thereof. , For example, polyethylenes such as high density, medium density, low density polyethylene and linear low density polyethylene, ultrahigh molecular weight polyethylene, ethylene vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, propylene homopolymer, Polypropylenes such as propylene-ethylene block copolymer or random polymer, propylene-ethylene-diene compound copolymer, polybutene-1, poly-4-methylpentene-1, and the like can be mentioned. Among these, crystalline polyethylene and crystalline polypropylene are preferable, and crystalline polypropylene is particularly preferable.
These polyolefin resins can be used singly or in combination of two or more.

(A) The polyolefin resin preferably has a melt flow rate (MFR) of 0.01 to 300 g / 10 minutes, and more preferably 0.1 to 100 g / 10 minutes. When the MFR is less than 0.01 g / 10 min, the flowability of the conductive composition is low, and extrusion molding and the like tend to be insufficient, which is not preferable. On the other hand, if the MFR exceeds 300 g / 10 min, the strength of the conductive composition tends to decrease, which is not preferable. In addition, "melt flow rate" here means the melt flow rate measured under 190 degreeC and a 21.2N load based on the method as described in ASTM-D1238.
The (i) polyolefin-based resin may be a polymer into which at least one functional group selected from the following functional group group X is introduced. By introducing a functional group, the adhesiveness between the conductive film of the present invention and a protective material made of glass, metal, or the like disposed above and below the conductive film of the present invention tends to be improved.
Here, the functional group X is a carboxyl group, an acid anhydride group, an epoxy group, a (meth) acryloyl group, an amino group, an alkoxysilyl group, a hydroxyl group, an isocyanate group, and an oxazoline group.

[(B) component]
The component (b) used in the conductive composition of the present invention is a hydrogenated thermoplastic elastomer.
(B) Preferred examples of hydrogenated thermoplastic elastomers include at least two polymer blocks (A) mainly composed of a structural unit derived from an aromatic vinyl compound and a structural unit derived from a conjugated diene compound. A hydrogenated block copolymer obtained by hydrogenating a block copolymer containing at least one polymer block (B) as a main component,
(1) The mass ratio ((A) / (B)) between the at least two polymer blocks (A) and the at least one polymer block (B) is 5/95 to 45/55,
(2) In each of the at least one polymer block (B), the content of the structural unit derived from the aromatic vinyl compound is 0 to 45% by mass, and the content of the structural unit derived from the conjugated diene compound is 55 to 55%. 100% by mass,
(3) The vinyl bond content in the whole of the at least one polymer block (B) is 60% or more,
(4) The weight average molecular weight in terms of polystyrene of the component (b) is 5 to 500,000,
(5) The hydrogenation rate of the component (b) is 80% or more,
(6) The melt flow rate measured under the conditions of 230 ° C. and 21.2 N load of the component (b) is 1 to 100 g / 10 minutes.
A hydrogenated block copolymer that satisfies all of the above conditions is mentioned.
In addition, the conditions of said (1)-(3) are conditions before hydrogenation. The above conditions (4) to (6) are conditions after hydrogenation.
The polymer block (A) is a polymer block mainly composed of structural units derived from an aromatic vinyl compound.
Examples of the aromatic vinyl compound used as a monomer for forming the polymer block (A) include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene. N, N-diethyl-p-aminoethyl styrene, N, N-diethyl-p-aminoethyl styrene, vinyl pyridine and the like, and styrene and α-methyl styrene are particularly preferable.
The polymer block (A) is preferably a polymer block consisting only of structural units derived from an aromatic vinyl compound.

The polymer block (B) is a polymer block mainly composed of structural units derived from a conjugated diene compound.
The proportion of the structural unit derived from the conjugated diene compound in the polymer block (B) is 55 to 100% by mass, preferably 65 to 100% by mass, more preferably 75 to 100% by mass, and particularly preferably 85 to 100% by mass. %. When the proportion is less than 55% by mass, the toughness of the conductive film is lowered.
The proportion of the structural unit derived from the aromatic vinyl compound in the polymer block (B) is 0 to 45% by mass, preferably 0 to 35% by mass, more preferably 0 to 25% by mass, and particularly preferably 0 to 15%. % By mass.
Examples of the conjugated diene compound used as a monomer for forming the polymer block (B) include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2 -Methyl-1,3-pentadiene, 1,3-hexadiene, 4.5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene and the like. Of these, 1,3-butadiene, isoprene and 1,3-pentadiene are preferable, and 1,3-butadiene is more preferable from the viewpoint of physical properties of the hydrogenated thermoplastic elastomer.
The example of an aromatic vinyl compound is the same as that of the above-mentioned polymer block (A).

The vinyl bond content (mass ratio) of the conjugated diene portion (for example, the total conjugated diene portion of the two polymer blocks (B)) in the entire at least one polymer block (B) is 60% or more, preferably 65 % Or more, more preferably 70% or more. When the content is less than 60%, the toughness of the conductive film is lowered. The “vinyl bond” refers to a monomer unit obtained by polymerizing a conjugated diene compound with a double bond at a 1,2-bond or a 3,4-bond position.
The vinyl bond content of the conjugated diene moiety in each of the at least one polymer block (B) is preferably the same as the numerical range of the vinyl bond content of the conjugated diene moiety in the entire polymer block (B).

A hydrogenated block copolymer can be obtained by hydrogenating the pre-hydrogenated block copolymer containing the polymer block (A) and the polymer block (B).
The block copolymer before hydrogenation is, for example, ABA, A- [BA] _n , or [AB] _n (where A is a polymer block (A), and B is a polymer). Block (B), n represents an integer of 1 or more) and the like. The upper limit of n in the above formula is not particularly limited, but is usually 5.
In the block copolymer before hydrogenation, the mass ratio of the polymer block (A) to the polymer block (B) (polymer block (A) / polymer block (B)) is 5/95 to 45/55. The ratio is preferably 5/95 to 40/60, more preferably 5/95 to 35/65, and particularly preferably 10/90 to 25/75. If the mass ratio is outside the above range, a viscosity suitable for extrusion molding or the like cannot be obtained, and problems such as reduced productivity and reduced toughness of the conductive film may occur.

(B) The hydrogenation rate of the double bond of the conjugated diene moiety in the hydrogenated block copolymer is 80% or more, preferably 85% or more, more preferably 90% or more, and particularly preferably 95% or more. When the hydrogenation rate is less than 80%, the toughness, heat resistance, weather resistance, ozone resistance and the like of the conductive composition are lowered.
(B) The polystyrene-converted weight average molecular weight of the hydrogenated block copolymer is 50,000 to 500,000, preferably 50,000 to 450,000, and more preferably 50,000 to 400,000. When the weight average molecular weight is less than 50,000, a conductive film excellent in toughness cannot be obtained. On the other hand, when the weight average molecular weight exceeds 500,000, the fluidity of the conductive composition is lowered, and a conductive film is produced. The moldability at the time of carrying out falls.
In addition, (b) the melt flow rate (MFR) of the hydrogenated block copolymer measured under conditions of 230 ° C. and 21.2 N load is 1 to 100 g / 10 minutes, preferably 1 to 80 g / 10 minutes. More preferably, it is 1-60 g / 10min, Most preferably, it is 1-45g / 10min. When the melt flow rate is less than 1 g / 10 min, the fluidity of the conductive composition is low, and extrusion molding and the like tend to be insufficient, which is not preferable. When the melt flow rate exceeds 100 g / 10 min, the strength of the conductive composition tends to decrease, which is not preferable.
The (b) hydrogenated block copolymer may be a polymer into which at least one functional group selected from the following functional group group X is introduced. By introducing a functional group, the adhesiveness between the conductive film of the present invention and a protective material made of glass, metal, or the like disposed above and below the conductive film of the present invention tends to be improved.
Here, the functional group X is a carboxyl group, an acid anhydride group, an epoxy group, a (meth) acryloyl group, an amino group, an alkoxysilyl group, a hydroxyl group, an isocyanate group, and an oxazoline group.

(B) As a specific method for producing a hydrogenated block copolymer, a polymer block (A) and a polymer block (B) are polymerized in a living anion polymerization using an organic alkali metal compound as an initiator in an organic solvent. Then, after obtaining a block copolymer (pre-hydrogenation block copolymer), hydrogenation is further performed on the block copolymer.
As the organic solvent, hydrocarbon solvents such as pentane, hexane, heptane, octane, methylcyclopentane, cyclohexane, benzene and xylene are used.
As the organic alkali metal compound which is a polymerization initiator, an organic lithium compound is preferable. As the organic lithium compound, an organic monolithium compound, an organic dilithium compound, or an organic polylithium compound is used. Specific examples thereof include ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, t-butyl lithium, hexamethylene dilithium, butadienyl lithium, and isoprenyl dilithium. And used in an amount of 0.02 to 0.2 parts by weight per 100 parts by weight of the monomer.
At this time, as a regulator of the microstructure, that is, the vinyl bond content of the conjugated diene moiety, Lewis bases such as ethers and amines, specifically diethyl ether, tetrahydrofuran, propyl ether, butyl ether, higher ethers, or ethylene glycol Polyethylene glycol ether derivatives such as dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, and triethylene glycol dimethyl ether. Examples of amines include tertiary amines such as tetramethylethylenediamine, pyridine, and tributylamine, which are used with the above organic solvents. .
Furthermore, the polymerization reaction is usually performed at −30 ° C. to 150 ° C.
Further, the polymerization may be carried out while controlling at a constant temperature, or may be carried out at an elevated temperature without removing heat.

The block copolymer before hydrogenation thus obtained may be a block copolymer in which a polymer molecular chain is extended or branched by adding a coupling agent.
As the coupling agent at this time, for example, diethyl adipate, divinylbenzene, tetrachlorosilicon, butyltrichlorosilicon, tetrachlorotin, butyltrichlorotin, dimethylchlorosilicon, tetrachlorogermanium, 1,2-dibromoethane, 1, Examples include 4-chloromethylbenzene, bis (trichlorosilyl) ethane, epoxidized linseed oil, tolylene diisocyanate, 1,2,4-benzene triisocyanate, and the like.
The bond content of the aromatic vinyl compound in the block copolymer is adjusted by the monomer supply amount at the time of polymerization in each stage, and the vinyl bond content of the conjugated diene compound is obtained by varying the components of the micro-adjusting agent. Adjusted. Furthermore, a weight average molecular weight and a melt flow rate are adjusted with the addition amount of a polymerization initiator, for example, n-butyllithium.

The hydrogenated block copolymer is obtained by dissolving the block copolymer before hydrogenation in an inert solvent and hydrogenating it in the presence of a hydrogenation catalyst under 20 to 150 ° C. and 1 to 100 kg / cm ² of pressurized hydrogen. Can be obtained.
Examples of the inert solvent used for hydrogenation include hydrocarbon solvents such as hexane, heptane, cyclohexane, benzene, toluene, and ethylbenzene, or polar solvents such as methyl ethyl ketone, ethyl acetate, ethyl ether, and tetrahydrofuran.
Examples of the hydrogenation catalyst include dicyclopentadienyl titanium halide, organic carboxylate nickel, nickel carboxylate and organometallic compounds of Groups I to III of the periodic table, carbon, silica, diatomaceous earth. Nickel, platinum, palladium, ruthenium, rhenium, rhodium metal catalysts and cobalt, nickel, rhodium, ruthenium complexes, or lithium aluminum hydride, p-toluenesulfonyl hydrazide, and Zr-Ti-Fe-V-Cr Examples thereof include hydrogen storage alloys such as alloys, Zr—Ti—Nb—Fe—V—Cr alloys, LaNi ₅ alloys, and the like.
The hydrogenation rate of the double bond of the conjugated diene part of the polymer block (B) of the hydrogenated block copolymer is determined by the hydrogenation catalyst, the amount of hydrogenated compound added, or the hydrogen pressure and reaction time during the hydrogenation reaction. It is adjusted by changing.
From the hydrogenated block copolymer solution, it is possible to remove catalyst residues, add a phenolic or amino antioxidant, and easily isolate the hydrogenated block copolymer from the polymer solution. it can.
Isolation of the hydrogenated block copolymer is carried out by, for example, a method in which acetone or alcohol is added to the copolymer solution to precipitate, a method in which the polymer solution is stirred in hot water, and the solvent is distilled off. be able to.

[(C) component]
The component (c) used in the conductive composition of the present invention is a conductive filler.
Examples of the conductive filler include conductive carbon black, carbon fiber, metal powder, metal oxide powder, and the like, preferably conductive carbon black or carbon fiber.
[Other optional ingredients]
Other optional components used in the conductive composition of the present invention include liquid additives such as paraffinic oil and liquid low molecular weight polyolefin. By adding the liquid additive, processability can be improved.
Moreover, various other additives can be added as long as the amount is within the range not impairing conductivity, toughness and flexibility. Such additives include antioxidants, weathering agents, metal deactivators, UV absorbers, light stabilizers, bleed / bloom inhibitors, sealability improvers, crystal nucleating agents, flame retardants, anti-blocking agents. Fungus, fungicide, dispersant, softener, anti-coloring agent, organic fiber, composite fiber, inorganic whisker, glass beads, glass balloon, glass flake, asbestos, mica, calcium carbonate, talc, silica, calcium silicate, hydro Mention may be made of fillers such as talcite, kaolin, diatomaceous earth, graphite, pumice, evo powder, cotton floc, cork powder, barium sulfate, polymer beads, or mixtures thereof, or other rubbery polymers. Specific examples of other rubbery polymers include SBR, NBR, BR, NR, IR, 1,2-polybutadiene, AR, CR, IIR and the like.

The conductive composition of the present invention can be obtained by melt-kneading the above components (a) to (c). For melt kneading, a pressure kneader kneader, a Banbury mixer, or the like can be used. Furthermore, it can be pelletized using a feeder ruder or the like after melt-kneading. By pelletizing, workability and the like when obtaining a film can be improved.
Alternatively, melt kneading and pelletization can be performed at once by using the above components (a) to (c) as materials and using a single screw extruder, twin screw extruder or the like as a means for melt kneading. .
The conductive composition obtained is (i) 1 to 99 parts by mass of a polyolefin-based resin, (b) 99 to 1 part by mass of a hydrogenated thermoplastic elastomer (however, (b) + (b) is 100 parts by mass) And (c) containing 1 to 100 parts by mass of a conductive filler.
(A) The compounding quantity of polyolefin-type resin is 1-99 mass parts in the total of 100 mass parts of (a) component and (b) component, Preferably it is 5-95 mass parts, More preferably, it is 15-90 mass parts. Particularly preferred is 30 to 85 parts by mass.
(A) If the compounding quantity of a component is less than 1 mass part, the composition suitable for extrusion molding etc. is difficult to be obtained.
(I) When the compounding quantity of a component exceeds 99 mass parts, it is difficult to obtain the composition excellent in toughness.
(C) The blending amount of the conductive filler is 1 to 100 parts by mass, preferably 3 to 80 parts by mass, and more preferably 5 to 70 parts by mass with respect to 100 parts by mass in total of the components (A) and (B). Part by mass. If the blending amount is less than 1 part by mass, desired conductivity cannot be obtained. On the other hand, if it exceeds 100 parts by mass, the extrusion moldability deteriorates and the toughness of the conductive film decreases.

[Conductive film]
The conductive film of the present invention is a film made of the above conductive composition.
The conductive film can be obtained, for example, by melting pellets made of the above conductive composition with an extruder or the like and then using a film take-up device or the like to form a film. As the extruder, for example, a T-die film molding extruder, an inflation molding extruder, or the like can be used. Alternatively, it is obtained by melting and rolling the pellet made of the above conductive composition with a high-temperature roll or the like and then forming a film using a film take-up device or the like. As said high temperature roll, a calender roll, a roll press machine, etc. can be used, for example.
Although the thickness of an electroconductive film is not specifically limited, For example, it is 10-200 micrometers.
The volume resistivity (electric resistivity) of the conductive film is 1 × 10 ³ Ω · cm or less, preferably 1 × 10 ² Ω · cm or less, more preferably 1 × 10 Ω · cm or less. When the value is 1 × 10 ³ Ω · cm or less, high conductivity can be obtained.
Hereinafter, “a × 10 ^b Ω · cm” may be expressed as “aE + 0b”.

  Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

[Production of hydrogenated block copolymer]
The hydrogenated block copolymer ((B) component) used for an electroconductive composition was manufactured by the method shown below.
(Production Example 1)
An autoclave with an internal volume of 50 liters was charged with 25 kg of degassed and dehydrated cyclohexane and 450 g of styrene, and then added with 300 g of tetrahydrofuran and 4.0 g of n-butyllithium, and adiabatic polymerization from 50 ° C. was performed for 20 minutes. After setting the reaction solution to 20 ° C., 4250 g of 1,3-butadiene was added to perform adiabatic polymerization. After the conversion rate is almost 100%, 300 g of styrene is further added to perform polymerization, and A-B-A (where A is a styrene homopolymer block and B is a butadiene homopolymer block). A block copolymer having the following structure was obtained.
Next, hydrogen gas was supplied at a pressure of 0.4 MPa-G, stirred for 20 minutes, and reacted with the polymer terminal lithium alive as a living anion to obtain lithium hydride. The reaction solution was brought to 90 ° C., tetrachlorosilane (1.6 g) was added, and the mixture was stirred for about 20 minutes, and then hydrogenated using a titanocene compound to obtain a hydrogenated block copolymer (Rho 1). It was.
(Production Example 2)
A-A-A (where A is a styrene homopolymer block and B is a butadiene-styrene copolymer block) in the same manner as in Production Example 1 except that the blending amount of monomers and the like is changed as appropriate. A block copolymer having the structure of Subsequently, hydrogenation was performed in the same manner as in Production Example 1 to obtain a hydrogenated block copolymer (B-2).
(Production Example 3)
A-A-B (where A is a styrene homopolymer block and B is a butadiene homopolymer block) in the same manner as in Production Example 1 except that the amount of the monomer and the like is appropriately changed. .) Was obtained. Subsequently, hydrogenation was performed in the same manner as in Production Example 1 to obtain a hydrogenated block copolymer (B-3).

The physical properties of the obtained hydrogenated block copolymers (B-1) to (B-3) or the block copolymer before hydrogenation are summarized in Table 1. The physical properties of the copolymer are evaluated by the following method.
(1) Mass ratio of polymer block A and polymer block B ("A / B ratio" in Table 1)
It calculated using the following formula | equation from the preparation amount of the raw material at the time of manufacturing a copolymer.
[A / B ratio] = (total charge of polymer block (A)) / (total charge of polymer block (B))
(2) Total aromatic vinyl compound unit content (“total bound styrene content” in Table 1)
It calculated from a 270 MHz and ¹ H-NMR spectrum using a carbon tetrachloride solution.
(3) Vinyl bond content in polymer block B ("(B) vinyl bond content in block" in Table 1)
The vinyl bond (1,2-bond and 3,4-bond) content was calculated by the Hampton method using infrared analysis.
(4) Content of aromatic vinyl compound in polymer block B ("(B) styrene content in block" in Table 1)
It calculated using the following formula | equation from the preparation amount of the raw material at the time of manufacturing a copolymer.
[Styrene content (mass%) in block B] = (total charge of aromatic vinyl compound contained in polymer block (B)) / (total charge of polymer block (B) as a whole) × 100
(5) Weight average molecular weight of hydrogenated block copolymer (“weight average molecular weight” in Table 1)
It calculated | required in polystyrene conversion using the gel permeation chromatography (room temperature GPC, column: Tosoh Corporation make, GMH-XL).
(6) Hydrogenation rate The hydrogenation rate of the conjugated diene compound unit was calculated from a 270 MHz, ¹ H-NMR spectrum using a carbon tetrachloride solution.
(7) Melt flow rate of hydrogenated block copolymer (“MFR” in Table 1)
According to JIS K7210, it measured on condition of 230 degreeC and a 21.2N load.

[Examples 1-5, Comparative Examples 1-5]
Each component was blended in a pressure kneader kneader at the ratio shown in Table 2, melt-kneaded, and further pelletized with a feeder ruder. Next, the obtained pellets were melted with a T-die film molding extruder, and then a conductive film was obtained with a film take-up device. The obtained film was evaluated for toughness and volume resistivity by the following methods. The results are shown in Table 2.
(Evaluation methods)
(Toughness)
In the 90 ° bending test, determination was made by the following evaluation method.
A: Good toughness, no cracking, and no stress relaxation.
○: There is no problem in toughness and there is no cracking, but there is some stress relaxation.
Δ: Almost no problem in toughness, but it may be bent.
X: Toughness is poor and cracks immediately.
(Volume resistivity)
The volume specific resistance value was measured using a Lorester manufactured by Mitsubishi Chemical Corporation.

  From Table 2, it can be seen that according to the composition of the present invention, a film that is suitable for production by extrusion molding and has both high conductivity (low volume resistivity) and high toughness can be obtained. On the other hand, in Comparative Example 1 which does not contain (B) component, and in Comparative Examples 3 to 5 using ethylene / propylene elastomer or ethylene / octene elastomer instead of (B) component, all are inferior in film toughness. I understand that. Moreover, it turns out that it is inferior to the toughness of a film also in the comparative example 2 using the hydrogenated block copolymer whose vinyl bond content in a (B) block is outside the range of this invention.

Claims (4)

(A) 1 to 99 parts by mass of polyolefin resin, (b) 99 to 1 part by mass of hydrogenated thermoplastic elastomer (provided that (a) + (b) = 100 parts by mass), and (c) conductivity. A conductive composition comprising 1 to 100 parts by mass of a conductive filler and having a volume resistivity of 10 ³ Ω · cm or less. The component (b) is composed mainly of at least two polymer blocks (A) mainly composed of structural units derived from aromatic vinyl compounds and at least one polymer composed mainly of structural units derived from conjugated diene compounds. A hydrogenated block copolymer obtained by hydrogenating a block copolymer containing the block (B),
(1) The mass ratio ((A) / (B)) between the at least two polymer blocks (A) and the at least one polymer block (B) is 5/95 to 45/55,
(2) In each of the at least one polymer block (B), the content of the structural unit derived from the aromatic vinyl compound is 0 to 45% by mass, and the content of the structural unit derived from the conjugated diene compound is 55 to 55%. 100% by mass,
(3) The vinyl bond content in the whole of the at least one polymer block (B) is 60% or more,
(4) The weight average molecular weight in terms of polystyrene of the component (b) is 5 to 500,000,
(5) The hydrogenation rate of the component (b) is 80% or more,
(6) The melt flow rate measured under the conditions of 230 ° C. and 21.2 N load of the component (b) is 1 to 100 g / 10 min.
The conductive composition according to claim 1, wherein all of the conditions are satisfied.   The conductive composition according to claim 1, wherein the component (c) is conductive carbon black or carbon fiber.   The electroconductive film which consists of an electroconductive composition of any one of Claims 1-3.