JP2011236366A - Thermoplastic elastomer composition and molded article thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoplastic elastomer composition capable of forming a heat-conductive member being excellent in molding processability, thermal conductivity, cold-resistance, close adhesion property, low paste remaining property and anti-pump out property, and to provide a molded article thereof.SOLUTION: The thermoplastic elastomer composition contains a hydrogenated diene-based copolymer in which a block copolymer represented by formula (a): [(i)-(ii)]-X is hydrogenated, 5-1,000 pts. of a liquid-like component (B) based on 100 pts. of the hydrogenated diene-based copolymer (A), and heat-conductive filler (C). In a polymer block (i), a vinyl bonding content is less than 25%, and in a polymer block (ii), a vinyl bonding content is 35% or more. In the thermoplastic elastomer composition, in the block copolymer, a content ratio of the polymer block (i) is 5-90 mass% of the total of the polymer block (i) and the polymer block (ii), and a coupling ratio is 70-90%. (In formula (a), X represents a coupling agent residual, and n represents 3 or 4).

Description

  The present invention relates to a thermoplastic elastomer composition and a molded article thereof. More specifically, the present invention relates to a thermoplastic elastomer composition used for heat dissipation measures for electronic devices and the like, and a molded product thereof.

  In recent years, with the downsizing and higher performance of electronic devices, the amount of heat generated from heat generating parts such as CPUs and LED boards has increased, resulting in decreased product performance, shortened product life, reduced safety (burns, fire), etc. This problem has become obvious, and it is important to take measures to dissipate the heat generated through the heat dissipating part such as a heat sink or a product housing.

  In general, materials for heat generating parts such as CPUs and LED substrates and materials for heat radiating parts such as heat sinks and product housings are materials with poor flexibility such as metals, ceramics, and resins. In addition, since there are irregularities on the surfaces of the heat generating part and the heat radiating part, a gap is formed between the heat generating part and the heat radiating part, which may deteriorate the heat conduction efficiency. Therefore, it is known to use a thermally conductive grease between the heat generating part and the heat radiating part in order to increase the adhesion between the heat generating part and the heat radiating part and conduct heat efficiently.

  As the thermally conductive grease, a thermally conductive grease is proposed in which a thermally conductive filler such as aluminum oxide, aluminum nitride, boron nitride, zinc oxide, silicon carbide or the like is added to silicone oil in order to increase thermal conductivity ( For example, see Patent Documents 1 and 2).

  However, such a heat conductive grease has a thermal expansion and thermal contraction due to heating and cooling, and warpage occurs due to a difference in coefficient of thermal expansion between the heat generating part and the heat radiating part. A phenomenon called “pump-out”, in which the thermal conductive grease flows out from between the heat generating portion and the heat radiating portion to reduce the thermal conductivity, is a problem. Further, when separating the heat generating part and the heat radiating part for repair or repair of electronic equipment, it is necessary to wipe off the heat conductive grease with an organic solvent or the like. In order to improve these pump-out and workability problems, development of a sheet-like heat conductive member having adhesiveness equivalent to that of the heat conductive grease is expected.

  As such a sheet-like heat conductive member, a heat conductive filler such as aluminum nitride or alumina is added to a material having a softening point at the operating temperature of an electronic device such as ethylene-vinyl acetate copolymer or wax. Thus, a material called a phase change sheet has been proposed that is excellent in adhesion at the operating temperature and is sheet-like and excellent in workability at room temperature (see, for example, Patent Documents 3 and 4).

Japanese Patent No. 3891969 Japanese Patent No. 2580348 Japanese Patent No. 3794996 Japanese Patent No. 4030399

  However, since the heat conductive member described in Patent Document 3 or 4 has a low material strength, the heat conductive sheet is damaged when the heat conductive member is peeled off from the heat generating part or the heat radiating part in a thin sheet shape, and a part thereof However, there is a problem that so-called “glue residue” occurs in the heat generating portion or the heat radiating portion.

  The present invention has been made in view of such problems of the prior art, and the subjects thereof are excellent moldability, thermal conductivity, cold resistance, adhesion, and pump-out resistance. An object of the present invention is to provide a thermoplastic elastomer composition capable of forming a heat conductive member excellent in low adhesive residue and a molded product thereof.

  As a result of intensive studies to achieve the above-mentioned problems, the inventors of the present invention have added a hydrogenated diene copolymer having a star-shaped block structure, a liquid component, and a thermally conductive filler to the thermoplastic elastomer composition. It has been found that the above-mentioned problems can be achieved by including them as essential elements, and the present invention has been completed.

  That is, according to the present invention, the following thermoplastic elastomer composition and molded product thereof are provided.

[1] (A) Polymer block (i) having a structural unit derived from the first conjugated diene compound, polymer block (ii) having a structural unit derived from the second conjugated diene compound, and coupling agent A hydrogenated diene copolymer having a residue and hydrogenated from a block copolymer represented by the following general formula (a), and (B) a softener, a plasticizer, and a liquid polymer At least one liquid component selected from the group, and (C) a thermally conductive filler, and the content ratio of the (B) liquid component is 100 parts by mass of the (A) hydrogenated diene polymer. The polymer block (i) is a polymer block having a vinyl bond content of less than 25%, and the polymer block (ii) has a vinyl bond content of 35%. With the polymer block being above Both the block copolymer has a content ratio of the polymer block (i) of 5 to 90% by mass with respect to the total of the polymer block (i) and the polymer block (ii), and A thermoplastic elastomer composition having a content of the polymer block (ii) of 10 to 95% by mass and a coupling rate of 70 to 90%.
[(I)-(ii)] _n -X (a)
(In general formula (A), (i) represents polymer block (i), (ii) represents polymer block (ii), X represents a coupling agent residue, and n represents 3 or 4 is shown.)

  [2] The thermoplastic elastomer composition according to [1], wherein the hydrogenated diene copolymer (A) has a hydrogen conversion rate of a double bond derived from the conjugated diene compound of 80% or more.

  [3] The thermoplastic elastomer composition according to [1] or [2], wherein the hydrogenated diene copolymer (A) has a weight average molecular weight of 50,000 to 700,000.

  [4] In the polymer block (i), the content ratio of structural units derived from 1,3-butadiene is 90% by mass or more of the total of all the structural units of the polymer block (i). ] The thermoplastic elastomer composition according to any one of [3].

  [5] In the polymer block (ii), the content ratio of the structural unit derived from the second conjugated diene compound is 50% by mass or more of the total of all the structural units of the polymer block (ii). The thermoplastic elastomer composition according to any one of [1] to [4].

  [6] The thermoplastic elastomer composition according to any one of [1] to [5], wherein the polymer block (ii) further contains a structural unit derived from a vinyl aromatic compound.

  [7] Any of [1] to [6], wherein the content ratio of the liquid component (B) is 20 to 500 parts by mass with respect to 100 parts by mass of the (A) hydrogenated diene copolymer. The thermoplastic elastomer composition described in 1.

  [8] The thermoplastic elastomer composition according to any one of [1] to [7], wherein the liquid component (B) includes the softening agent and the liquid polymer.

  [9] The thermoplastic elastomer composition according to any one of [1] to [8], wherein the liquid polymer is liquid polybutene.

  [10] The thermoplastic elastomer composition according to any one of [1] to [9], further including (D) a surface treatment agent.

  [11] The thermoplastic elastomer composition according to [10], wherein the content ratio of the (D) surface treatment agent is 0.05 to 5 parts by mass with respect to 100 parts by mass of the (C) thermally conductive filler. object.

  [12] The thermoplastic elastomer composition according to [10] or [11], wherein the (D) surface treatment agent is a saturated fatty acid.

  [13] A molded article comprising the thermoplastic elastomer composition according to any one of [1] to [12].

  [14] The molded product according to [13], which is a heat conductive sheet having a thickness of 30 to 3000 μm.

  The thermoplastic elastomer composition of the present invention and the molded product thereof have excellent molding processability, thermal conductivity, cold resistance, adhesion, and pump-out resistance, and excellent thermal conductivity with low adhesive residue. The effect that a member can be formed is produced. Specifically, the thermoplastic elastomer composition of the present invention comprises (A) a hydrogenated diene copolymer, so that the processability, cold resistance, adhesion, and low paste of the heat conductive member formed are formed. Residual properties and pump-out resistance can be improved. Moreover, the thermoplastic elastomer composition of this invention can improve thermal conductivity by including the (C) thermal conductive filler.

  Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the following embodiments, and based on ordinary knowledge of those skilled in the art without departing from the spirit of the present invention. It should be understood that modifications, improvements, and the like appropriately added to the embodiments described above fall within the scope of the present invention.

[1] Thermoplastic elastomer composition:
The thermoplastic elastomer composition of the present invention is a composition comprising (A) a hydrogenated diene copolymer, (B) a liquid component, and (C) a thermally conductive filler. The details will be described below.

[1-1] (A) Hydrogenated diene copolymer:
(A) The hydrogenated diene copolymer includes a polymer block (i) having a structural unit derived from the first conjugated diene compound, and a polymer block (ii) having a structural unit derived from the second conjugated diene compound. And a block copolymer represented by the following general formula (a) is hydrogenated, and the polymer block (i) has a vinyl bond content of less than 25%. The polymer block (ii) is a polymer block having a vinyl bond content of 35% or more, and the block copolymer comprises the polymer block (i) and the polymer block. The content of the polymer block (i) is 5 to 90% by mass, and the content of the polymer block (ii) is 10 to 95% by mass with respect to the total of the blocks (ii). Couple 'S modulus is hydrogenated diene copolymer is 70 to 90%.
[(I)-(ii)] _n -X (a)
(In general formula (a), (i) represents the polymer block (i), (ii) represents the polymer block (ii), X represents a coupling agent residue, and n represents 3 or 4 is shown.)

  As described above, the (A) hydrogenated diene copolymer is a polymer block (ii) in which the hydrogenated copolymer is centered on the coupling agent residue (X) in the general formula (a). It has a so-called star-shaped structure in which three or four are coupled from the side. Therefore, such a (A) hydrogenated diene copolymer is a material having an excellent balance between material strength and flexibility. By including such a (A) hydrogenated diene copolymer, the thermoplastic elastomer composition of the present invention exhibits good unevenness followability with respect to the unevenness of the heat-generating part and the heat-dissipating part. It also has excellent cold resistance, adhesion, low adhesive residue, and pump-out resistance.

  In the present specification, the vinyl bond content is a value calculated by the Hampton method using infrared analysis. For infrared analysis, an infrared absorption analyzer (“FT-720” (trade name) manufactured by HORIBA) was used. In this specification, when it is described as 1,2-vinyl bond, 3,4-vinyl bond is also included. That is, for example, 1,2-vinyl bond and 3,4-vinyl bond in 1,3-butadiene are not distinguished.

[1-1-1] Block copolymer (a):
The block copolymer (a) is a block copolymer represented by the general formula (a).

  In the block copolymer (a), the content of the polymer block (i) is 5 to 90% by mass with respect to the total of the polymer block (i) and the polymer block (ii), and 10 to 80 It is preferable that it is mass%. That is, the content ratio of the polymer block (ii) is 10 to 95% by mass and preferably 20 to 90% by mass with respect to the total of the polymer block (i) and the polymer block (ii). . When the content of the polymer block (i) is less than 5% by mass (that is, the content of the polymer block (ii) is more than 95% by mass), the mechanical strength of the block copolymer (a) decreases. End up. On the other hand, when the content of the polymer block (i) is more than 90% by mass (that is, the content of the polymer block (ii) is less than 10% by mass), the strength of the block copolymer (a) is excessively high. It will rise.

  The polymer block (i) is a polymer block having a structural unit derived from the first conjugated diene compound and having a vinyl bond content of less than 25%. Examples of the first conjugated diene compound 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 can be mentioned. Among these, 1,3-butadiene is particularly preferable.

  The content ratio of the structural unit derived from the first conjugated diene compound in the polymer block (i) is preferably 90% by mass or more of the total of all the structural units of the polymer block (i), and is 95% by mass. It is still more preferable that it is above. When the content ratio of the structural unit derived from the first conjugated diene compound is within the above range, a molded product having excellent low adhesive residue can be obtained.

  In the polymer block (i), the content ratio of the structural units derived from 1,3-butadiene is preferably 90% by mass or more, and 95% by mass or more of the total of all the structural units of the polymer block (i). More preferably. When the content of the structural unit derived from 1,3-butadiene in the polymer block (i) is within the above range, (A) the hydrogenated polymer block in the hydrogenated diene copolymer Since (i) has a structure similar to that of low density polyethylene, a molded product excellent in low adhesive residue can be obtained.

  The vinyl bond content of the polymer block (i) is less than 25%, preferably less than 20%, and more preferably less than 15%. When the vinyl bond content of the polymer block (i) is 25% or more, the melting point of the crystal of the (A) hydrogenated diene copolymer is remarkably lowered, and the mechanical strength tends to be lowered.

  The weight average molecular weight of the polymer block (i) is preferably 25,000 to 630,000, and more preferably 30,000 to 480,000. When the weight average molecular weight of the polymer block (i) is within the above-mentioned range, the molecular weight of the obtained block copolymer (a) can be made appropriate.

  In addition, in this specification, a weight average molecular weight is the value calculated | required in polystyrene conversion by the gel filtration chromatography (GPC) analysis. For GPC analysis, a GPC apparatus (“HLC-8120GPC” (trade name) manufactured by Tosoh Finechem Corporation, column: “GMH-XL” (trade name) manufactured by Tosoh Corporation) was used.

  The polymer block (ii) is a polymer block having a structural unit derived from the second conjugated diene compound and having a vinyl bond content of 35% or more. Examples of the second conjugated diene compound 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 can be mentioned. Among these, 1,3-butadiene, isoprene and 1,3-pentadiene are preferable, and 1,3-butadiene is more preferable. In addition, the polymer block (ii) may have 1 type independently among these 2nd conjugated diene compounds, and may have 2 or more types.

  In the polymer block (ii), the content ratio of the structural unit derived from the second conjugated diene compound is preferably 50% by mass or more of the total of all the structural units of the polymer block (ii). More preferably, it is at least mass%. When the content of the structural unit derived from the second conjugated diene compound is within the above range, (A) the hydrogenated polymer block (ii) in the hydrogenated diene copolymer is a rubber. Since the structure is similar to that of the ethylene-butene copolymer, a molded product having excellent flexibility can be formed.

  The polymer block (ii) is preferably a polymer block further containing a structural unit derived from a vinyl aromatic compound in addition to the structural unit derived from the second conjugated diene compound. Specific examples of such vinyl aromatic compounds include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, p-ethylstyrene, divinylbenzene, 1,1-diphenylstyrene, vinylnaphthalene, vinyl. Anthracene, N, N-diethyl-p-aminoethylstyrene, vinylpyridine and the like can be mentioned. Among these, styrene is preferable.

  In the polymer block (ii), the content ratio of the structural unit derived from the vinyl aromatic compound is preferably 35% by mass or less of the total of all the structural units of the polymer block (ii), and is 30% by mass or less. More preferably, it is particularly preferably 25% by mass or less. By increasing the content ratio of the structural unit derived from the vinyl aromatic compound within a range not exceeding 35% by mass, the mechanical strength of the molded article comprising the thermoplastic elastomer composition of the present invention is improved, and (B ) Liquid component leaching (bleeding) can be suppressed, that is, it is excellent in cold resistance. Moreover, the low temperature characteristic (cold resistance) of a thermoplastic elastomer composition will fall that the content rate of the structural unit derived from a vinyl aromatic compound is more than 35 mass%.

  The vinyl bond content of the polymer block (ii) is 35% or more, preferably 40 to 95%, more preferably 40 to 90%, and particularly preferably 45 to 80%. When the vinyl bond content of the polymer block (ii) is less than 35%, the crystallization of the polymer block (ii) proceeds at a low temperature. Therefore, from the thermoplastic elastomer composition of the present invention or a molded product thereof (B) Leaching (bleeding) of liquid components occurs and cold resistance is reduced.

  The weight average molecular weight of the polymer block (ii) is preferably 25,000 to 650,000, and more preferably 30,000 to 540,000. When the weight average molecular weight of the polymer block (ii) is within the above-mentioned range, the molecular weight of the obtained block copolymer (a) can be made appropriate.

  A portion of the block copolymer (a) comprising the polymer block (i) and the polymer block (ii) (hereinafter also simply referred to as “polymer block portion”), that is, in the general formula (a), [ The method for polymerizing the moiety represented by (i)-(ii)] is not particularly limited. For example, in an inert organic solvent, the first and second conjugated diene compounds, and the first and second Other monomers copolymerizable with the conjugated diene compound can be polymerized by living anion polymerization using an organic alkali metal compound as a polymerization initiator.

  Examples of the inert organic solvent used in the polymerization reaction include aliphatic hydrocarbon solvents such as pentane, hexane, heptane, and octane; alicyclic hydrocarbon solvents such as cyclopentane, methylcyclopentane, cyclohexane, and methylcyclohexane; benzene, Aromatic hydrocarbon solvents such as xylene, toluene, and ethylbenzene can be listed.

  Examples of the organic alkali metal compound used as the polymerization initiator include organic lithium compounds and organic sodium compounds. Among these, organic lithium compounds such as n-butyllithium, s-butyllithium, and t-butyllithium can be preferably used. There is no restriction | limiting in particular about the usage-amount of an organic alkali metal compound, Although the usage-amount can be adjusted suitably as needed, The quantity of 0.02-15 mass% is used per 100 mass% of monomer components. Preferably, an amount of 0.03 to 5% by mass is used.

  The polymerization temperature is preferably −10 to 150 ° C., more preferably 0 to 120 ° C. It is desirable to replace the polymerization atmosphere with an inert gas such as nitrogen. The polymerization pressure is not particularly limited as long as it is performed within a range of pressure sufficient to maintain the monomer and solvent in a liquid phase under the above polymerization conditions.

  Further, in the process of polymerizing the polymer block portion of the block copolymer (a), the method of introducing the monomer of each compound into the polymerization system is not particularly limited, and is batch, continuous, intermittent, or The method which combined these can be mentioned. Furthermore, the number and type of polymerization containers, the method for charging the monomer, and the like when polymerizing the polymer block portion of the block copolymer (a) are obtained. (A) Hydrogenated diene copolymer It can be appropriately selected so that the physical properties of the coalescence, (A) a hydrogenated diene copolymer, a molded article made of this composition, and the like are preferable.

In the block copolymer (a), the above-described polymer block portion is subjected to a coupling reaction using a coupling agent, whereby three or four molecular chains composed of the polymer block portion are coupled via a coupling residue. The block copolymer is bonded to each other and can be represented by the following general formula (a).
[(I)-(ii)] _n -X (a)
(In general formula (a), (i) represents the polymer block (i), (ii) represents the polymer block (ii), X represents a coupling agent residue, and n represents 3 or 4 is shown.)

  Examples of the coupling agent include 1,2,4-trivinylbenzene, epoxidized 1,2-polybutadiene, epoxidized soybean oil, epoxidized linseed oil, benzene-1,2,4-triisocyanate, 1, 1,2,2-tetrachloroethane, 1,4-bis (trichloromethyl) benzene, trichlorosilane, methyltrichlorosilane, butyltrichlorosilane, tetrachlorosilane, (dichloromethyl) trichlorosilane, hexachlorodisilane, tetraethoxysilane, tetrachloro Tin, 1,3-dichloro-2-propanone, etc. can be mentioned. Among these, epoxidized 1,2-polybutadiene, trichlorosilane, methyltrichlorosilane, and tetrachlorosilane are preferable.

  The coupling rate in the coupling reaction is 70 to 90%, preferably 70 to 85%, more preferably 70 to 83%, and particularly preferably 70 to 80%. When the coupling rate is within the above range, a molded product having an excellent balance between molding processability and low adhesive residue can be molded. Further, if the coupling rate is less than 70%, the amount of the block copolymer (a) produced is insufficient, so the mechanical strength of the molded product obtained using the thermoplastic elastomer composition is low and low. It becomes inferior to adhesive residue. On the other hand, when the coupling rate is more than 90%, productivity and workability in the production of a molded product on an industrial scale are lowered.

  In the present specification, the coupling rate is determined by (A) gel filtration chromatography (GPC) peak analysis of the hydrogenated diene copolymer. In the reaction solution after the coupling reaction, the unreacted block copolymer ( It is a ratio calculated from the peak area ratio of the block copolymer (a) produced by coupling with the polymer block part of a). In addition, for a copolymer having a unimodal molecular weight distribution, the block copolymer (a) produced by coupling with the weight average molecular weight of the polymer block portion of the block copolymer (a) before coupling is produced. The coupling rate was calculated from the weight average molecular weight. The weight average molecular weight was determined by GPC analysis.

  The block copolymer (a) may be a modified block polymer modified with a functional group. Examples of such a functional group include at least one functional group selected from the group consisting of a carboxyl group, an acid anhydride group, a hydroxyl group, an epoxy group, a halogen atom, an amino group, an isocyanate group, a sulfonyl group, and a sulfonate group. Can be mentioned. Examples of the modification method include conventionally known methods. The content ratio of the functional group in the modified block polymer is preferably 0.01 to 10.0 mol% of the total of the structural units constituting the block copolymer (a), and is preferably 0.10 to 8. It is more preferable that it is 00 mol%, and it is especially preferable that it is 0.15-5.00 mol%.

  The monomer for introducing the functional group is not particularly limited, but acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic anhydride, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, hydroxyethyl methacrylate, Hydroxypropyl methacrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, and dimethylaminoethyl methacrylate are preferred.

[1-1-2] Hydrogenation:
(A) The hydrogenated diene copolymer can be produced by hydrogenating the above-mentioned block copolymer (a).

  There is no restriction | limiting in particular about the method and reaction conditions of hydrogenation, For example, it carries out in the presence of a hydrogenation catalyst under 20-150 degreeC and hydrogen pressurization of 0.1-10 MPa. In this case, the hydrogenation rate can be appropriately adjusted by changing the amount of the hydrogenation catalyst, the hydrogen pressure during the hydrogenation reaction, or the reaction time.

  Examples of the hydrogenation catalyst include titanium (Ti), vanadium (V), cobalt (Co), nickel (Ni), zirconium (Zr), ruthenium (Ru), rhodium (Rh), palladium (Pd), hafnium ( Examples thereof include compounds containing metal atoms such as Hf), rhenium (Re), and platinum (Pt).

  More specifically, metallocene compounds containing metal atoms such as Ti, Zr, Hf, Co, Ni, Pd, Pt, Ru, Rh, and Re; metal atoms such as Pd, Ni, Pt, Rh, and Ru Supported heterogeneous catalyst in which is supported on a carrier such as carbon, silica, alumina, diatomaceous earth; homogeneous Ziegler type that combines organic salt of metal atom such as Ni, Co or acetylacetone salt and reducing agent such as organic aluminum Catalysts; organometallic compounds or complexes containing Ru, Rh, etc .; fullerenes or carbon nanotubes occluded with hydrogen. Among these, a metallocene compound containing any metal atom of Ti, Zr, Hf, Co, and Ni is preferable in that it can be hydrogenated in a homogeneous system in an inert organic solvent, and any of Ti, Zr, and Hf is preferable. The metallocene compound containing a metal atom is more preferable. A hydrogenation catalyst obtained by reacting a titanocene compound with an alkyl lithium is particularly preferable because it is an inexpensive and industrially useful catalyst. In addition, these hydrogenation catalysts may be used individually by 1 type, or may use 2 or more types together.

  The amount of the hydrogenation catalyst to be added is not particularly limited and can be appropriately selected according to the type of polymer, the type of hydrogenation catalyst, the hydrogenation rate, and the like. Usually, the first conjugated diene compound and The total amount of the second conjugated diene compound is preferably 0.005 to 0.05 mol%, more preferably 0.008 to 0.03 mol%, and 0.01 to 0.02 mol%. It is particularly preferred that

  After hydrogenation using such a hydrogenation catalyst, the catalyst residue is removed if necessary, or a phenol-based or amine-based antioxidant is added, and then (A) hydrogenation is performed from the reaction solution. A diene copolymer is isolated. (A) Isolation of the hydrogenated diene copolymer can be carried out, for example, by adding acetone, alcohol or the like to the reaction solution for precipitation, or by pouring the reaction solution into hot water with stirring and distilling off the solvent. It can be carried out.

  (A) The hydrogenated diene copolymer is composed of a 1,2-vinyl bond contained in the polymer block (i) in the block copolymer (a), and the block copolymer (a). 80% or more of the total 1,2-vinyl bond contained in the polymer block (ii) is preferably hydrogenated, more preferably 90% or more is hydrogenated, and 95 to 100%. Is preferably hydrogenated. That is, the hydrogenation rate of the (A) hydrogenated diene copolymer is preferably 80% or more, more preferably 90% or more, and particularly preferably 95 to 100%. When the hydrogenation rate is low (less than 80%), the thermal stability and durability of the (A) hydrogenated diene copolymer tend to be lowered.

In the present specification, the hydrogenation rate was calculated from ¹ H-NMR spectrum analysis at 270 MHz using a carbon tetrachloride solution. For ¹ H-NMR spectrum analysis, a nuclear magnetic resonance apparatus (“JEOL EX-270” (trade name) manufactured by JEOL Ltd.) was used.

  (A) The weight average molecular weight of the hydrogenated diene copolymer is preferably 50,000 to 700,000, and more preferably 100,000 to 600,000. When the weight average molecular weight is less than 50,000, heat resistance and mechanical strength tend to be lowered. On the other hand, if the weight average molecular weight is more than 700,000, the moldability may be lowered.

[1-2] (B) Liquid component:
(B) A liquid component is at least 1 type selected from the group which consists of a softener, a plasticizer, and a liquid polymer. Details will be described below.

[1-2-1] Softener:
The softening agent is a liquid component used to soften the thermoplastic elastomer composition of the present invention and improve the adhesion to a heat generating part and a heat radiating part of an electronic device or the like.

  Such softeners include, for example, mineral oils such as paraffinic oils, naphthenic oils and aromatic oils, synthetic oils such as ethylene / α-olefin oligomers, fatty acids such as oleic acid and ricinoleic acid, and castor oil And vegetable oils such as cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, and peanut oil.

[1-2-2] Plasticizer:
The plasticizer is a liquid component used for imparting thermoplasticity to the thermoplastic elastomer composition of the present invention and improving the adhesion to the heat generating part and the heat radiating part at the operating temperature of the electronic device or the like.

  Examples of such plasticizers include phthalic acid derivatives, isophthalic acid derivatives, tetrahydrophthalic acid derivatives, adipic acid derivatives, sebacic acid derivatives, fumaric acid derivatives, citric acid derivatives, azelaic acid derivatives, phosphoric acid derivatives, maleic acid derivatives. And various fatty acid derivatives.

[1-2-3] Liquid polymer:
The liquid polymer is a liquid component used for improving the molding processability and adhesion of a molded product formed from the thermoplastic elastomer composition of the present invention.

  Examples of such a liquid polymer include liquid polybutadiene, liquid isoprene, liquid polybutene, liquid styrene / butadiene rubber, polyisobutylene, and silicone oil. These liquid polymers may be modified.

  (B) As a liquid component, since the thermoplastic elastomer composition of this invention can be made excellent in a softness | flexibility and adhesiveness, the liquid component which combined the softening agent and the liquid polymer is preferable. In addition, liquid prebutene is particularly preferable from the viewpoint that the heat resistance of the molded product can be suppressed.

  In the thermoplastic elastomer composition of the present invention, the addition amount of the liquid component (B) is 5 to 1000 parts by mass with respect to 100 parts by mass of the (A) hydrogenated diene copolymer, and 10 to 800 parts by mass. It is preferable that it is 20-500 mass parts. (B) If the addition amount of the liquid component is less than 5 parts by mass, the flexibility of the thermoplastic elastomer composition may be reduced. On the other hand, when the added amount of the liquid component (B) is more than 1000 parts by mass, the mechanical strength of the thermoplastic elastomer composition is lowered, and the molding processability and the low adhesive residue tend to be deteriorated.

[1-3] (C) Thermally conductive filler:
(C) A heat conductive filler is added in order to provide heat conductivity to the thermoplastic elastomer composition of this invention.

  (C) Examples of the thermally conductive filler include carbon materials, metal materials, ceramic materials, silica materials, and composite materials thereof.

  Specific examples of carbon materials include furnace blacks such as ketjen black; carbon blacks such as acetylene black, channel black and gas black; carbon fibers such as PAN carbon fibers, pitch carbon fibers and rayon carbon fibers; Examples thereof include graphite such as graphite, flaky graphite, massive graphite, and earthy graphite; diamond, fullerene, carbon microcoil, carbon nanotube, graphene, and the like.

  Specific examples of metal materials include silver powder, gold powder, copper powder, iron powder, stainless steel powder, nickel powder, aluminum powder, platinum powder, and other metal powders; alumina, magnesium oxide, zinc oxide, antimony oxide, indium oxide, and the like. Metal oxides: Metal fibers such as copper fibers, stainless steel fibers, aluminum fibers and nickel fibers can be mentioned.

  Specific examples of the ceramic material include ceramics such as boron nitride, aluminum nitride, silicon nitride, alumina-titanium carbide ceramic, zirconia ceramic, and silicon carbide.

  Specific examples of the silica-based material include silica powder such as quartz, crystalline silica, and amorphous silica.

  These (C) thermally conductive fillers may be used alone or in combination of two or more.

  For the purpose of improving the wettability with the (A) hydrogenated diene copolymer serving as a matrix, it is preferable to use a surface-treated (C) thermally conductive filler.

  The shape of the particles constituting each of the above-mentioned (C) thermally conductive fillers is not particularly limited, and examples thereof include a spherical shape, a needle shape, a fiber shape, a scale shape, a dendritic shape, a flat plate shape, and an indefinite shape. it can. When the aspect ratio of the particles constituting the thermally conductive filler (C) such as boron nitride or carbon fiber is larger than 1 and has anisotropy of thermal conductivity, electric field, magnetic field, shear field, gravity field, and their By the combination, (C) the thermally conductive filler can be oriented, and thermal conductivity anisotropy can be imparted to the resulting molded article of the thermoplastic elastomer composition. Specific examples of the shear field include extrusion molding, roll molding, injection molding, and foam molding.

  The number average particle diameter of the particles constituting each of the above (C) thermally conductive fillers is preferably 0.01 to 500 μm, more preferably 0.1 to 400 μm, and 1 to 300 μm. Is particularly preferred. (C) When the number average particle diameter of the particles constituting the thermally conductive filler is too small, the viscosity of the resulting elastomer composition increases, and the processability tends to be remarkably lowered. On the other hand, if the number average particle diameter of the particles constituting the thermally conductive filler (C) is too large, the design of the molded article of the thermoplastic elastomer composition obtained tends to be lowered.

  In the thermoplastic elastomer composition of the present invention, the amount of (C) thermally conductive filler added is preferably 20 to 80 parts by volume, preferably 30 to 75 parts by volume, relative to 100 parts by volume of the thermoplastic elastomer composition. It is more preferable that it is 35 to 70 parts by volume. (C) If the amount of the thermally conductive filler added is too small, the thermal conductivity of the thermoplastic elastomer composition tends to be too low, and if it is excessive, the flexibility and workability of the thermoplastic elastomer composition deteriorate. It is not preferable because it tends to be.

  Moreover, flame retardance can be imparted to the resulting thermoplastic elastomer composition by using a metal hydroxide such as aluminum hydroxide or magnesium hydroxide as the thermally conductive filler (C). Furthermore, in order to improve flame retardancy, brominated flame retardants such as tetrabromobisphenol A and decabromodiphenyl ether, red phosphorus, aromatic phosphate ester, aromatic condensed phosphate ester, halogenated phosphate ester as necessary Phosphorus flame retardants such as antimony trioxide, silicone flame retardants and the like may be further added. Further, short silicon nitride fibers or the like may be added to prevent drip.

[1-4] (D) Surface treatment agent:
The thermoplastic elastomer composition of the present invention further contains (D) a surface treatment agent in addition to the above-mentioned (A) hydrogenated diene copolymer, (B) liquid component, and (C) thermally conductive filler. It is preferable. The thermoplastic elastomer composition of the present invention contains (D) a surface treatment agent, whereby the surface of the above-mentioned (C) thermal conductive filler is coated, so that (C) the thermal conductive filler (A ) The wettability with the hydrogenated diene copolymer is improved, and the dispersibility of the (C) thermally conductive filler in the thermoplastic elastomer composition can be improved. Therefore, the thermal conductivity and flexibility of the thermoplastic elastomer composition can be improved.

  (D) As a surface treating agent, a fatty acid, fatty acid ester, fatty acid metal salt, hydrogenated oil, a silane coupling agent, a titanate coupling agent, etc. can be mentioned.

  Examples of the fatty acid include stearic acid, oleic acid, palmitic acid, linoleic acid, lauric acid, caprylic acid, behenic acid, montanic acid, castor oil, linseed oil, and the like.

  Examples of fatty acid esters include methyl laurate, methyl myristate, methyl palmitate, methyl stearate, methyl oleate, methyl erucate, methyl behenate, butyl laurate, butyl stearate, isopropyl myristate, isopropyl palmitate , Monoesters such as octyl palmitate, octyl palm fatty acid, octyl stearate, special beef tallow fatty acid octyl ester, lauryl laurate, long stearyl stearate, long chain fatty acid higher alcohol ester, behenyl behenate, cetyl myristate; Polyol long chain fatty acid ester, neopentyl polyol long chain fatty acid ester partially esterified product, neopentyl polyol fatty acid ester, neopentyl polyol medium chain fatty acid ester Ether, neopentyl polyol C9 chain fatty acid esters, dipentaerythritol long chain fatty acid ester, and special fatty acid esters such as complex medium chain fatty acid esters.

  Examples of the fatty acid metal salt include metal salts such as stearic acid, oleic acid, palmitic acid, linoleic acid, lauric acid, caprylic acid, behenic acid, and montanic acid. These metals include sodium (Na), potassium (K), aluminum (Al), calcium (Ca), magnesium (Mg), zinc (Zn), barium (Ba), cobalt (Co), and tin. (Sn), titanium (Ti), iron (Fe), etc. can be mentioned.

  As hardened oil, beef tallow hardened oil, castor hardened oil, etc. can be mentioned, for example.

  Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, vinyltrichlorosilane, vinyltriacetoxysilane, N- (β-aminoethyl) -γ-aminopropyl. Trimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, β- (3,4-epoxycyclohexyl) Ethyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltris (β-methoxyethoxy) silane, γ-mercaptopropyltrimethoxysilane, methyltrimethoxylane, methyltriethoxy Orchids, hexamethyldisilazane, .gamma. anilino trimethoxysilane, mention may be made of N- [beta-(N- vinyl benzal amino) ethyl] -γ- aminopropyltrimethoxysilane hydrochloride and the like.

  Examples of titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl tri (N-aminoethyl / aminoethyl) titanate, diisopropyl bis (dioctyl phosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis ( Ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (ditridecyl) phosphite titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, bis (dioctyl pyrophosphate) ethylene titanate be able to.

  Among these (D) surface treatment agents, saturated fatty acids are preferable because of their excellent heat resistance. In addition, these (D) surface treating agents may be used individually by 1 type, or may use 2 or more types together.

  In the thermoplastic elastomer composition of the present invention, the amount of (D) the surface treatment agent added is preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the (C) thermal conductive filler. More preferably, the amount is 0.05 to 2 parts by mass. (D) When the addition amount of a surface treating agent is too small, it exists in the tendency for the addition effect of (D) surface treating agent not to be seen. On the other hand, if the addition amount of (D) the surface treatment agent is excessive, the mechanical strength of the thermoplastic elastomer composition is lowered and bleeding occurs, and the moldability, cold resistance, and low adhesive residue tend to deteriorate. is there.

[1-5] Additive:
The thermoplastic elastomer composition of the present invention can further contain various additives as required.

  Examples of such additives include foaming agents, lubricants, heat stabilizers, light stabilizers such as HALS, weathering agents, metal deactivators, ultraviolet absorbers, light stabilizers, and copper stabilizers. Antibacterial agent, antifungal agent, dispersant, flame retardant, tackifier, colorant such as titanium oxide, carbon black, organic pigment, fiber such as glass cloth, aramid fiber, inorganic whisker such as potassium titanate whisker, glass Beads, glass balloons, glass flakes, asbestos, mica, calcium carbonate, talc, calcium silicate, hydrotalcite, kaolin, diatomaceous earth, pumice, evo powder, cotton flock, cork powder, barium sulfate, fluororesin, polymer beads, polyolefin Fillers such as wax, cellulose powder, rubber powder, wood powder or mixtures thereof, ethylene / propylene copolymer It can be mentioned isobutylene-isoprene copolymers, rubbers such as silicone rubber, polyethylene, polypropylene, thermoplastic resins such as ethylene-vinyl acetate copolymer.

[2] Molded product:
The molded article of the present invention can be produced by molding the above-mentioned thermoplastic elastomer composition. The shape of the molded product is not particularly limited and can be various shapes. Among them, for example, in order to obtain a heat conductive member used for heat dissipation measures such as electronic equipment, the thickness is 30 to 3000 μm. It is particularly preferable to form a sheet, that is, a heat conductive sheet.

  There is no restriction | limiting in particular as a method of shape | molding a molded article, A conventionally well-known method can be applied, For example, roll press molding, extrusion molding, press molding, injection molding, roll molding etc. can be mentioned.

[2-1] Thermally conductive sheet:
The heat conductive sheet can be used as, for example, a heat conductive member used for heat dissipation measures for electronic devices and the like, and efficiently conducts heat generated from the heat generating portion to the heat radiating portion, that is, has excellent heat conductivity. The heat conductive member is excellent in cold resistance, adhesion, low adhesive residue, and pump-out resistance.

  The thickness of the heat conductive sheet is preferably 30 to 3000 μm, more preferably 30 to 500 μm, and particularly preferably 30 to 200 μm. By setting the thickness of the heat conductive sheet within the above-described range, it is possible to form a heat conductive sheet that is excellent in heat conductivity, low glue residue, and pump-out resistance.

  The heat conductive sheet of the present invention may further include other members. For example, since the heat conductive sheet of the present invention has self-adhesiveness, a protective film may be provided on at least one surface of the heat conductive sheet for the purpose of improving the handleability. That is, a protective film may be provided on one side or both sides of the heat conductive sheet of the present invention. A heat conductive sheet provided with such a protective film is used by peeling the protective film and exposing the surface of the heat conductive sheet in use. The protective film may be a single layer or a multilayer.

  The constituent material of the protective film is not particularly limited. As a constituent material of the protective film, for example, paper, polyethylene, polypropylene, ethylene / propylene copolymer, polybutene, ethylene / vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, α-olefin alone such as ionomer Examples thereof include polymers or copolymers, polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyimide, and thermoplastic elastomers. The thickness of the protective film is preferably 10 to 1000 μm, more preferably 10 to 500 μm, and particularly preferably 10 to 100 μm.

  In order to facilitate the peeling of the protective film, a silicone-based or fluorine-based release coating layer can be provided between the protective film and the heat conductive sheet of the present invention. Furthermore, the surface of the heat conductive sheet of the present invention provided with a protective film may have irregularities.

  Furthermore, the heat conductive sheet of the present invention may have a support layer. That is, the heat conductive sheet of this invention may be arrange | positioned on both surfaces of the support layer. The constituent material of the support layer is not particularly limited. Examples of the constituent material of the support layer include glass cloth, metal mesh, and the like in addition to the constituent materials of the protective film described above. Moreover, although the thickness of this support layer is the same as that of a protective film, it is preferable that it is thin from a viewpoint of heat conductive efficiency.

  It is particularly preferable that the heat conductive sheet of the present invention is formed by roll press molding, and the thermoplastic elastomer composition is formed in a state where both surfaces are held between two protective films of PET film. By forming in this way, it prevents the heat conductive sheet from adhering to the roll press machine and prevents the processability from degrading and the heat conductive sheets from sticking to each other. The handleability of the sheet can be improved.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. A method for measuring various physical properties and a method for evaluating various properties are shown below.

[Hydrogenation rate (%)]:
Calculation was performed from ¹ H-NMR spectrum analysis at 270 MHz using a carbon tetrachloride solution. For ¹ H-NMR spectrum analysis, a nuclear magnetic resonance apparatus (“JEOL EX-270” (trade name) manufactured by JEOL Ltd.) was used.

[Weight average molecular weight]:
The weight average molecular weight is a value determined in terms of polystyrene by gel filtration chromatography (GPC) analysis. For GPC analysis, a GPC apparatus (“HLC-8120GPC” (trade name) manufactured by Tosoh Finechem Corporation, column: “GMH-XL” (trade name) manufactured by Tosoh Corporation) was used.

[Vinyl bond content (%)]:
The vinyl bond content is a value calculated by the Hampton method using infrared analysis. For infrared analysis, an infrared absorption analyzer (“FT-720” (trade name) manufactured by HORIBA) was used.

[Coupling rate (%)]:
(A) By the gel filtration chromatography (GPC) peak analysis of the hydrogenated diene copolymer, it is coupled with the polymer block portion of the unreacted block copolymer (a) in the reaction solution after the coupling reaction, It is a value calculated from the peak area ratio with the generated block copolymer (a). For copolymers having a unimodal molecular weight distribution, the coupling rate was calculated from the weight average molecular weight before coupling and the weight average molecular weight after coupling.

[Melt flow rate (g / 10 min)]:
The measurement was performed at 230 ° C. and 21.2 N in accordance with JIS K7210. Note that the temperature (° C.) and the load (N) were appropriately changed depending on the object to be measured.

[Formability]:
Using each thermoplastic elastomer composition as a protective film, a PET film (“Purex A31” (trade name) and “Purex A43” (trade name) manufactured by Teijin DuPont), 180 ° C., 1 m / min Is formed using a roll press machine (manufactured by Hirano Giken Kogyo Co., Ltd., roll diameter 300 mm, effective surface length 500 mm, surface roughness 0.1 s), and is a press-formed sheet (thermal conductivity) having a thickness of 50 μm and width 400 mm Sheet). In this case, the thickness tolerance is within 10% of the average thickness, and the case where a sheet that does not cause material destruction even when the protective film is peeled is evaluated as “excellent in workability”, and in the table In the case where a sheet having a thickness tolerance of more than 10% of the average thickness is obtained as an “evaluation result”, and when the protective film is peeled off after molding, the sheet is broken, etc. The case where at least one of the cases was not able to be evaluated was evaluated as “inferior in molding processability” and indicated as “B” as the “evaluation result” in the table. In the table, the measured thickness tolerance value is shown in the row of “thickness tolerance (μm)”. In addition, each following evaluation method evaluated using the thing similar to the heat conductive sheet shape | molded using each above-mentioned thermoplastic elastomer composition in the state which peeled the protective film.

  However, the press molded sheets (heat conductive sheets) molded in Examples 15, 16, and 17 were molded into sheets having thicknesses of 30 μm, 200 μm, and 3000 μm, respectively.

[Thermal conductivity (W / Km)]:
Based on JIS R1611, the thermal conductivity of each thermal conductive sheet was measured. The measurement results (W / Km) are shown in the table.

[Cold resistance]:
Each heat conductive sheet was put into a low-temperature tank (manufactured by Tabai Co., Ltd.), and a cold resistance test was conducted at -40 ° C for 500 hours. Subsequently, each heat conductive sheet was taken out from the low temperature tank, and the external appearance of the sheet was visually observed. In this case, the case where no bleed of the liquid component is observed in the heat conductive sheet is evaluated as “excellent in cold resistance”, and is indicated by “A” in the table, and the case where the bleed of the liquid component is observed in the heat conductive sheet. It was evaluated as “inferior in cold resistance” and indicated by “B” in the table.

[Adhesion]:
Each heat conductive sheet cut into 10 mm × 100 mm using a pressure roller (roller mass 2000 g) conforming to JIS Z0237 is bonded to a SUS304 plate polished with No. 240 according to JIS R6001, and the heat conductive sheet A laminated body was obtained. The thermally conductive sheet laminate was tilted so that the bonding surface was vertical, and the bonding surface was visually observed. The case where no detachment or displacement of the heat conductive sheet is observed is evaluated as “excellent in adhesion”, and is indicated by “A” in the table, and the case where detachment or displacement of the heat conductive sheet is observed is referred to as “adhesion”. Inferior to "" and indicated by "B" in the table.

[Low glue residue]:
In the evaluation of adhesion, the heat conductive sheet laminate bonded to the SUS304 plate was put into a gear oven (“ACR60” (trade name) manufactured by Toyo Seiki Seisakusho) set at 80 ° C. for 500 hours. After taking out from the gear oven, it was left still for one day under the conditions of 23 ° C. and 50% relative humidity. Then, the heat conductive sheet was peeled from the SUS304 board. At this time, the case where no adhesive residue was observed on the SUS304 plate was evaluated as “excellent in low adhesive residue”, indicated by “A” in the table, and the case where adhesive residue was observed on the SUS304 plate was indicated as “low adhesive residue”. It was inferior in property ”and indicated by“ B ”in the table.

[Pump-out resistance]:
Each thermally conductive sheet was sandwiched between 5 mm thick glass plates to form a glass laminate. A magic outline was drawn on the surface of the glass laminate along the shape of the thermally conductive sheet. Next, this glass laminate is put into a thermal shock apparatus (“TSA-41L-A” (trade name) manufactured by Espec Corp.) and heated at 100 ° C. for 1 hour and cooled at −40 ° C. for 1 hour for one cycle. As a result, a heat cycle test of 100 cycles was performed. The shape of the heat conductive sheet after the test was visually observed. The case where the shape of the heat conductive sheet did not protrude from the contour of the glass laminate surface was evaluated as “excellent pump-out resistance”, indicated by “A” in the table, and the shape of the heat conductive sheet was glass The case where it protruded from the contour of the laminate surface was evaluated as “inferior in pump-out resistance” and indicated by “B” in the table.

(Synthesis Example 1 Production of Hydrogenated Diene Copolymer (A-1))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 900 g of 1,3-butadiene, and 3.3 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 50 ° C., 130 g of tetrahydrofuran and 2100 g of 1,3-butadiene were added to perform adiabatic polymerization. After 50 minutes, 1.8 g of tetrachlorosilane was added and reacted for 30 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was brought to 90 ° C., 7.2 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-1) having a [(i)-(ii)] ₄ -Si structure was obtained.

  The hydrogenated diene copolymer (A-1) obtained had a hydrogenation rate of 99% and a weight average molecular weight of 330,000. The first stage polybutadiene block of the block copolymer before hydrogenation (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the vinyl bond content of the second stage polybutadiene block (polymer block (ii)) of the block copolymer before hydrogenation. Was 50% and the coupling rate was 80%. Moreover, the melt flow rate measured at 230 degreeC and 98.1N of the hydrogenated diene copolymer (A-1) was 0.5 g / 10min.

(Synthesis Example 2 Production of Hydrogenated Diene Copolymer (A-2))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 1200 g of 1,3-butadiene, and 2.9 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 5 ° C., and 340 g of tetrahydrofuran and 1800 g of 1,3-butadiene were added to perform adiabatic polymerization. After 30 minutes, 1.8 g of tetrachlorosilane was added and reacted for 30 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was brought to 90 ° C., 6.6 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. [(I)-(ii)] _4- Si structure hydrogenated diene copolymer (A-2) was obtained.

  The resulting hydrogenated diene copolymer (A-2) has a hydrogenation rate of 99% and a weight average molecular weight of 320,000. The first stage polybutadiene block of the block copolymer before hydrogenation (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the vinyl bond content of the second stage polybutadiene block (polymer block (ii)) of the block copolymer before hydrogenation. Was 80%, and the coupling rate was 75%. The melt flow rate of the hydrogenated diene copolymer (A-2) measured at 230 ° C. and 21.2 N was 4.5 g / 10 min.

(Synthesis Example 3 Production of Hydrogenated Diene Copolymer (A-3))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 900 g of 1,3-butadiene, and 2.6 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 45 ° C., and 34 g of tetrahydrofuran, 1600 g of 1,3-butadiene, and 500 g of styrene were added to perform adiabatic polymerization. After 30 minutes, 1.8 g of tetrachlorosilane was added and reacted for 30 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was set to 90 ° C., 6.2 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-3) having a [(i)-(ii)] ₄ -Si structure was obtained.

  The hydrogenated diene copolymer (A-3) obtained had a hydrogenation rate of 99% and a weight average molecular weight of 300,000, and the first stage polybutadiene block of the block copolymer before hydrogenation. (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the second stage poly (butadiene / styrene copolymer) block (polymer block ( The vinyl bond content of ii)) was 37%, and the coupling rate was 78%. Moreover, the melt flow rate measured at 230 degreeC and 98.1N of the hydrogenated diene copolymer (A-3) was 0.3 g / 10min.

(Synthesis Example 4 Production of Hydrogenated Diene Copolymer (A-4))
24 kg of cyclohexane, 100 g of tetrahydrofuran, 900 g of 1,3-butadiene, and 3.3 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 40 ° C. After completion of the reaction, the temperature was set to 5 ° C., and 340 g of tetrahydrofuran and 2100 g of 1,3-butadiene were added to perform adiabatic polymerization. After 30 minutes, 1.8 g of tetrachlorosilane was added and reacted for 30 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was brought to 90 ° C., 7.2 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-4) having a [(i)-(ii)] ₄ -Si structure as a coalescence was obtained.

  The hydrogenated diene copolymer (A-4) obtained had a hydrogenation rate of 99% and a weight average molecular weight of 330,000. The first stage polybutadiene block of the block copolymer before hydrogenation. The vinyl bond content of the (polymer block (i)) is 45% (per terminal), and the vinyl bond content of the second stage polybutadiene block (polymer block (ii)) of the block copolymer before hydrogenation. Was 80%, and the coupling rate was 75%. Further, the melt flow rate of the hydrogenated diene copolymer (A-4) measured at 230 ° C. and 21.2 N was 6.5 g / 10 minutes.

(Synthesis Example 5 Production of Hydrogenated Diene Copolymer (A-5))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 900 g of 1,3-butadiene, and 3.3 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 30 ° C., and 26 g of tetrahydrofuran and 2100 g of 1,3-butadiene were added to perform adiabatic polymerization. After 30 minutes, 1.8 g of tetrachlorosilane was added and reacted for 30 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was brought to 90 ° C., 7.2 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-5) having a [(i)-(ii)] ₄ -Si structure was obtained.

  The hydrogenated diene copolymer (A-5) thus obtained had a hydrogenation rate of 99% and a weight average molecular weight of 320,000, and the first stage polybutadiene block of the block copolymer before hydrogenation. (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the second stage poly (butadiene / styrene copolymer) block (polymer block ( The vinyl bond content of ii)) was 33%, and the coupling rate was 79%. Further, the melt flow rate of the hydrogenated diene copolymer (A-5) measured at 230 ° C. and 98.1 N was 0.3 g / 10 min.

(Synthesis Example 6 Production of Hydrogenated Diene Copolymer (A-6))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 900 g of 1,3-butadiene, and 3.3 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 50 ° C., 130 g of tetrahydrofuran and 2100 g of 1,3-butadiene were added to perform adiabatic polymerization. After 50 minutes, 2.1 g of tetrachlorosilane was added and reacted for 180 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was brought to 90 ° C., 7.2 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-6) having a [(i)-(ii)] ₄ -Si structure as a coalescence was obtained.

  The hydrogenated diene copolymer (A-6) obtained had a hydrogenation rate of 99% and a weight average molecular weight of 360,000. The first stage polybutadiene block of the block copolymer before hydrogenation (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the vinyl bond content of the second stage polybutadiene block (polymer block (ii)) of the block copolymer before hydrogenation. Was 50% and the coupling rate was 95%. The melt flow rate of the hydrogenated diene copolymer (A-6) measured at 230 ° C. and 98.1 N was less than 0.1 g / 10 minutes.

(Synthesis Example 7 Production of Hydrogenated Diene Copolymer (A-7))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 900 g of 1,3-butadiene, and 3.3 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 50 ° C., 130 g of tetrahydrofuran and 2100 g of 1,3-butadiene were added to perform adiabatic polymerization. After 50 minutes, 1.3 g of tetrachlorosilane was added and reacted for 30 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was brought to 90 ° C., 7.2 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-7) having a [(i)-(ii)] ₄ -Si structure was obtained.

  The hydrogenated diene copolymer (A-7) obtained had a hydrogenation rate of 99% and a weight average molecular weight of 270,000. The first stage polybutadiene block of the block copolymer before hydrogenation (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the vinyl bond content of the second stage polybutadiene block (polymer block (ii)) of the block copolymer before hydrogenation. Was 50% and the coupling rate was 65%. Further, the melt flow rate of the hydrogenated diene copolymer (A-7) measured at 230 ° C. and 98.1 N was 2.0 g / 10 minutes.

(Synthesis Example 8 Production of Hydrogenated Diene Copolymer (A-8))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 900 g of 1,3-butadiene and 2.3 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters substituted with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 50 ° C., 130 g of tetrahydrofuran and 2100 g of 1,3-butadiene were added to perform adiabatic polymerization. After 50 minutes, 1.9 g of methyldichlorosilane was added and reacted for 30 minutes. After completion of the reaction, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was set to 90 ° C., 5.7 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-8) having a structure of [(i)-(ii)] ₂ -Si was obtained.

  The hydrogenated diene copolymer (A-8) obtained had a hydrogenation rate of 99% and a weight average molecular weight of 320,000. The first stage polybutadiene block of the block copolymer before hydrogenation (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the vinyl bond content of the second stage polybutadiene block (polymer block (ii)) of the block copolymer before hydrogenation. Was 50% and the coupling rate was 65%. The melt flow rate of the hydrogenated diene copolymer (A-8) measured at 230 ° C. and 21.2 N was 1.0 g / 10 min.

(Synthesis Example 9 Production of Hydrogenated Diene Copolymer (A-9))
24 kg of cyclohexane, 1.2 g of tetrahydrofuran, 900 g of 1,3-butadiene, and 3.3 g of n-butyllithium were charged into a reaction vessel having an internal volume of 50 liters purged with nitrogen, and adiabatic polymerization was performed from 70 ° C. After completion of the reaction, the temperature was set to 50 ° C., 130 g of tetrahydrofuran and 2100 g of 1,3-butadiene were added to perform adiabatic polymerization. After 50 minutes, hydrogen gas was supplied at a pressure of 0.4 MPaG, stirred for 20 minutes, reacted with lithium ions at the polymerization terminal, and the living anion polymerization reaction was stopped. The reaction solution was brought to 90 ° C., 7.2 g of tetrachlorosilane was added, and the mixture was stirred for about 20 minutes. Then, a hydrogenation catalyst was added, and a hydrogenation reaction was performed at a hydrogen pressure of 0.8 MPa for 2 hours. When the absorption of hydrogen is completed, the reaction solution is returned to room temperature and normal pressure and extracted from the reaction vessel.Then, the reaction solution is stirred into water and the solvent is removed by steam distillation to remove the hydrogenated diene heavy polymer. A hydrogenated diene copolymer (A-9) having a structure (i)-(ii) was obtained.

  The hydrogenated diene copolymer (A-9) obtained had a hydrogenation rate of 99% and a weight average molecular weight of 110,000, and the first stage polybutadiene block of the block copolymer before hydrogenation. (Polymer block (i)) has a vinyl bond content of 15% (per terminal), and the vinyl bond content of the second stage polybutadiene block (polymer block (ii)) of the block copolymer before hydrogenation. Was 50%. The melt flow rate of the hydrogenated diene copolymer (A-9) measured at 230 ° C. and 21.2 N was 70 g / 10 min.

Example 1
Hydrogenated diene copolymer (A-1) 100 parts by mass, liquid component (B-1-1) 200 parts by mass, thermal conductive filler (C-1) 1242 parts by mass, surface treatment agent (D-1) 1.8 parts by mass and 0.3 parts by mass of the anti-aging agent were charged into a pressure type kneader (capacity 1.5 liter, manufactured by Moriyama Co., Ltd.) previously heated to 150 ° C. A kneaded material in a molten state was obtained by kneading for 20 minutes at 40 rpm (shearing speed 200 / second) until each component was uniformly dispersed. This kneaded product was used as the thermoplastic elastomer composition of Example 1. Various evaluations were performed on the obtained thermoplastic elastomer composition of Example 1. Table 1 shows the formulation of the thermoplastic elastomer composition of Example 1 and the evaluation results. In addition, the blending ratio (volume%) of (C) thermal conductive filler relative to the total of the blending components in the blending formulation of the thermoplastic elastomer composition (in Table 1, “(C) blending ratio of thermal conductive filler (volume %))) Is also shown in Table 1.

(Examples 2 to 17 and Comparative Examples 1 to 11)
Except having set it as the compounding prescription shown in Table 1 and Table 2, it carried out similarly to Example 1, and obtained with the thermoplastic elastomer composition of each Example 2-17 and Comparative Examples 1-11. Various evaluation was performed about each obtained thermoplastic elastomer composition. These evaluation results are shown in Table 1 or 2, respectively.

(Comparative Example 12)
100 parts by mass of liquid component (B-1-1), 379 parts by mass of thermally conductive filler (C-1), 0.6 part by mass of surface treatment agent (D-1), 0.1 part by mass of anti-aging agent, A heat conductive grease was obtained by putting in a planetary mixer preheated to 100 ° C. and stirring at 40 rpm for 20 minutes. The obtained heat conductive grease was sandwiched between two glass plates having a thickness of 5 mm, and the heat conductive grease was compressed until the thickness of the heat conductive grease reached 50 μm, and used for evaluation of pump-out resistance. Table 2 shows the formulation and evaluation results of the thermally conductive grease.

  In addition, the hydrogenated diene copolymer (A-10) and the olefin polymer (A-11), (B) liquid component, and (C) thermally conductive filler described in the formulation of Table 1 and Table 2. (D) As the surface treating agent and the anti-aging agent, those shown below were used.

Hydrogenated diene copolymer (A-10): polystyrene-poly (ethylene-ethylene / propylene) block-polystyrene (“SEPTON 4077” (trade name) manufactured by Kuraray Co., Ltd.), melt flow rate (230 ° C., 98.1 N) (Less than 0.1 g / 10 minutes, styrene content: 33% by mass)
Olefin polymer (A-11): ethylene-vinyl acetate copolymer ("Evaflex EV150" (trade name) manufactured by Mitsui DuPont Polychemical Co., Ltd.), melt flow rate (190 ° C, 21.2N) 30 g / 10 Min, vinyl acetate content 33% by mass, softening temperature 32 ° C)

Liquid component (B-1-1): mineral oil softener (“PW-380” (trade name) manufactured by Idemitsu Kosan Co., Ltd., kinematic viscosity at 40 ° C .: 381.6 mm ² / sec)
Liquid component (B-1-2): Synthetic mineral oil-based softener (“Linearlendimer A-2020H” (trade name) manufactured by Idemitsu Kosan Co., Ltd., kinematic viscosity at 40 ° C .: 5.0 mm ² / sec)
Liquid component (B-2-1): Liquid polybutene (“Nisseki Polybutene HV-1900” (trade name) manufactured by Nippon Oil Corporation, kinematic viscosity at 40 ° C .: 160,000 mm ² / sec)
Liquid component (B-2-2): terminal hydroxyl group-modified liquid isoprene (“Epol” (trade name) manufactured by Idemitsu Kosan Co., Ltd., viscosity at 30 ° C .: 75 Pa · sec)

Thermally conductive filler (C-1): Aluminum hydroxide (“BF083” (trade name) manufactured by Nippon Light Metal Co., Ltd., average particle size: 10 μm)
Thermally conductive filler (C-2): Aluminum oxide (“Admafine AO509” (trade name) manufactured by Admatechs, average particle size: 10 μm)
Thermally conductive filler (C-3): Boron nitride (“DENCABORON NITRIDE JP75” (trade name) manufactured by Denka, average particle size: 25 μm)
Thermally conductive filler (C-4): carbon fiber (“Rahima A301” (trade name) manufactured by Teijin Ltd., average fiber diameter: 8 μm, average fiber length: 200 μm)

Surface treatment agent (D-1): Stearic acid ("Lunac S-50V" (trade name) manufactured by Kao Corporation)
Anti-aging agent: pentaerythritol tetrakis [3- (3,5-ditert-butyl-4-hydroxyphenyl) propionate (“Irganox 1010” (trade name) manufactured by Ciba Japan)

  From the results shown in Tables 1 and 2, the thermoplastic elastomer compositions of Examples 1 to 17 are more moldable, heat conductive, cold resistant than the thermoplastic elastomer compositions of Comparative Examples 1 to 12. It is clear that the adhesiveness, low adhesive residue, and pump-out resistance are excellent.

  Since the thermoplastic elastomer composition of Comparative Example 1 did not contain the liquid component (B), the heat conductive sheet made of the thermoplastic elastomer composition of Comparative Example 1 was inferior in adhesion. In the thermoplastic elastomer composition of Comparative Example 2, since the blending ratio of (B) liquid component is excessive with 1150 parts by mass with respect to 100 parts by mass of (A) hydrogenated diene copolymer, the protective film is formed after molding. When the material was peeled, material destruction occurred, and the heat conductive sheet made of the thermoplastic elastomer composition of Comparative Example 2 was inferior in moldability. Moreover, since the thermoplastic elastomer composition of Comparative Example 3 did not contain a thermally conductive filler, the thermally conductive sheet made of the thermoplastic elastomer composition of Comparative Example 3 was inferior in thermal conductivity.

  Since the hydrogenated diene copolymer (A-4) contained in the thermoplastic elastomer composition of Comparative Example 4 has a high vinyl bond content of 40% in the polymer block (i), the hydrogenated diene copolymer The mechanical strength of (A-4) was low, and the heat conductive sheet made of the thermoplastic elastomer composition of Comparative Example 4 was inferior in low adhesive residue and pump-out resistance.

  The hydrogenated diene copolymer (A-5) contained in the thermoplastic elastomer composition of Comparative Example 5 has a low vinyl bond content of 33% in the polymer block (ii), and the thermoplastic elastomer composition of Comparative Example 5 In the heat conductive sheet made of a material, bleeding occurred and the cold resistance was inferior.

  The hydrogenated diene copolymer (A-6) contained in the thermoplastic elastomer composition of Comparative Example 6 has a high coupling rate of 95%, and the thickness tolerance of the thermal conductive sheet exceeds 10% of the average thickness. Therefore, the heat conductive sheet made of the thermoplastic elastomer composition of Comparative Example 6 was inferior in moldability.

  The hydrogenated diene copolymer (A-7) contained in the thermoplastic elastomer composition of Comparative Example 7 has a coupling rate as low as 65%, and the amount of the block copolymer (a) produced is insufficient. Therefore, the heat conductive sheet made of the thermoplastic elastomer composition of Comparative Example 7 has low mechanical strength and is inferior in low adhesive residue.

  The hydrogenated diene copolymer (A-8) contained in the thermoplastic elastomer composition of Comparative Example 8 has two coupled copolymers, a coupling rate as low as 65%, and a block copolymer. Since the production amount of the polymer (a) was insufficient, the heat conductive sheet made of the thermoplastic elastomer composition of Comparative Example 8 had low mechanical strength and poor low adhesive residue.

  The hydrogenated diene copolymer (A-9) contained in the thermoplastic elastomer composition of Comparative Example 9 is not coupled and is a polymer block portion of the low molecular weight block copolymer (a). Therefore, the heat conductive sheet which consists of a thermoplastic-elastomer composition of the comparative example 9 was inferior to low paste remaining property and pump-out resistance.

  The hydrogenated diene copolymer (A-10) contained in the thermoplastic elastomer composition of Comparative Example 10 is a conventionally known polystyrene-poly (ethylene / propylene) block copolymer, and is outside the scope of the present invention. Therefore, the heat conductive sheet made of the thermoplastic elastomer composition of Comparative Example 10 was inferior in low adhesive residue.

  The thermoplastic elastomer composition of Comparative Example 11 is a conventionally known phase change sheet that is solid at room temperature and melts at a high temperature in a heat cycle test, but a hydrogenated diene copolymer is outside the scope of the present invention. It was inferior to cold resistance, low adhesive residue, and pump-out resistance.

  Since Comparative Example 12 was a grease-like composition containing no (A) hydrogenated diene copolymer, it was inferior in pump-out resistance.

  The thermoplastic elastomer composition of the present invention can be suitably used as a material for forming a heat conductive member used for heat dissipation measures for electronic devices and the like.

Claims (14)

(A) a polymer block (i) having a structural unit derived from the first conjugated diene compound, a polymer block (ii) having a structural unit derived from the second conjugated diene compound, and a coupling agent residue A hydrogenated diene copolymer obtained by hydrogenating a block copolymer represented by the following general formula (a);
(B) at least one liquid component selected from the group consisting of softeners, plasticizers, and liquid polymers;
(C) a heat conductive filler,
The content ratio of the (B) liquid component is 5 to 1000 parts by mass with respect to 100 parts by mass of the (A) hydrogenated diene polymer,
The polymer block (i) is a polymer block having a vinyl bond content of less than 25%, and the polymer block (ii) is a polymer block having a vinyl bond content of 35% or more,
The block copolymer has a content ratio of the polymer block (i) of 5 to 90% by mass with respect to the total of the polymer block (i) and the polymer block (ii), and A thermoplastic elastomer composition having a polymer block (ii) content of 10 to 95% by mass and a coupling rate of 70 to 90%.
[(I)-(ii)] _n -X (a)
(In general formula (A), (i) represents polymer block (i), (ii) represents polymer block (ii), X represents a coupling agent residue, and n represents 3 or 4 is shown.)   The thermoplastic elastomer composition according to claim 1, wherein the hydrogenated diene copolymer (A) has a hydrogen conversion rate of a double bond derived from the conjugated diene compound of 80% or more.   The thermoplastic elastomer composition according to claim 1 or 2, wherein the hydrogenated diene copolymer (A) has a weight average molecular weight of 50,000 to 700,000.   The content ratio of the structural unit derived from 1,3-butadiene in the polymer block (i) is 90% by mass or more of the total of all the structural units of the polymer block (i). The thermoplastic elastomer composition according to any one of the above.   The content ratio of the structural unit derived from the second conjugated diene compound in the polymer block (ii) is 50% by mass or more of the total of all the structural units of the polymer block (ii). 5. The thermoplastic elastomer composition according to any one of 4 above.   The thermoplastic elastomer composition according to any one of claims 1 to 5, wherein the polymer block (ii) further contains a structural unit derived from a vinyl aromatic compound.   The heat according to any one of claims 1 to 6, wherein a content ratio of the (B) liquid component is 20 to 500 parts by mass with respect to 100 parts by mass of the (A) hydrogenated diene copolymer. Plastic elastomer composition.   The thermoplastic elastomer composition according to any one of claims 1 to 7, wherein the liquid component (B) includes the softening agent and the liquid polymer.   The thermoplastic elastomer composition according to any one of claims 1 to 8, wherein the liquid polymer is liquid polybutene.   (D) The thermoplastic elastomer composition according to any one of claims 1 to 9, further comprising a surface treating agent.   The thermoplastic elastomer composition according to claim 10, wherein the content ratio of the (D) surface treatment agent is 0.05 to 5 parts by mass with respect to 100 parts by mass of the (C) thermal conductive filler.   The thermoplastic elastomer composition according to claim 10 or 11, wherein the (D) surface treatment agent is a saturated fatty acid.   A molded article comprising the thermoplastic elastomer composition according to any one of claims 1 to 12.   The molded article according to claim 13, which is a heat conductive sheet having a thickness of 30 to 3000 μm.