Thermoplastic elastomer composition and method for producing a thermoplastic elastomer composition

Abstract

The present invention provides a thermoplastic elastomer composition that exhibits excellent scratch resistance and can form a low-gloss appearance, as well as a method for producing the same. [Solution] The present disclosure relates to a thermoplastic elastomer composition comprising a first composition containing an olefin resin (A), an ethylene-α-olefin copolymer (B), and a crosslinking agent (F), and a second composition containing a hydrogenated block copolymer (C) having at least one block mainly composed of conjugated diene monomer units and at least one block mainly composed of vinyl aromatic monomer units, wherein the content of component (B) is 10 to 180 parts by mass per 100 parts by mass of component (A), the content of component (C) is 170 to 500 parts by mass per 100 parts by mass of component (A), and the ratio W1 / W0 of the sum of the content of component (B) and the content of component (C) to the gel content W1 is 0.01 to 0.70, and a method for producing the same.

Claims

1. A thermoplastic elastomer composition comprising the following first composition and the following second composition, The thermoplastic elastomer composition contains 10 to 180 parts by mass of ethylene-α-olefin copolymer (B) per 100 parts by mass of olefin resin (A). The hydrogenated block copolymer (C) contained in the thermoplastic elastomer composition, which has at least one block mainly composed of conjugated diene monomer units and at least one block mainly composed of vinyl aromatic monomer units, is 170 to 500 parts by mass per 100 parts by mass of olefin resin (A). The sum of the content of the ethylene-α-olefin copolymer (B) and the content of the hydrogenated substance (C) in the thermoplastic elastomer composition is W. 0 (mass%), gel content W 1 (As mass%) Ratio W 1 / W 0 A thermoplastic elastomer composition characterized by having a value of 0.01 to 0.70; [First composition] A composition containing an olefin resin (A), an ethylene-α-olefin copolymer (B), and a crosslinking agent (F). [Second composition] A composition containing a hydrogenated block copolymer (C) having at least one block mainly composed of conjugated diene monomer units and at least one block mainly composed of vinyl aromatic monomer units, characterized in that the amount of hydrogenated block copolymer (C) contained in the second composition is 30 parts by mass or more per 100 parts by mass of olefin resin (A) contained in the thermoplastic elastomer composition.

2. The thermoplastic elastomer composition according to claim 1, wherein the hydrogenated substance (C) is a styrene-based block copolymer.

3. The thermoplastic elastomer composition according to claim 1 or 2, wherein the amount of hydrogenated substance (C) contained in the thermoplastic elastomer composition is 180 to 250 parts by mass per 100 parts by mass of the olefin resin (A).

4. The first composition is obtained by melt-kneading the olefin resin (A), the ethylene-α-olefin copolymer (B), and the crosslinking agent (F), The thermoplastic elastomer composition according to any one of claims 1 to 3, wherein the thermoplastic elastomer composition is obtained by melt-kneading the first composition and the second composition.

5. Having either (i) or (ii) below, (i) A step of dynamically crosslinking an olefin resin (A) and an ethylene-α-olefin copolymer (B) using a crosslinking agent (F), then adding a hydrogenated substance (C) downstream of the same extruder and melt-kneading the mixture, and then removing the thermoplastic elastomer composition from the extruder. (ii) A step of dynamically crosslinking an olefin resin (A) and an ethylene-α-olefin copolymer (B) using a crosslinking agent (F), removing the crosslinked body from the extruder after the crosslinking reaction is complete, remelting the crosslinked body and a hydrogenated substance (C), and extruding to obtain a thermoplastic elastomer composition. The amount of the ethylene-α-olefin copolymer (B) contained in the thermoplastic elastomer composition is 10 to 180 parts by mass per 100 parts by mass of the olefin resin (A). The amount of the hydrogenated substance (C) contained in the thermoplastic elastomer composition is 170 to 500 parts by mass per 100 parts by mass of the olefin resin (A), The sum of the content of the ethylene-α-olefin copolymer (B) and the content of the hydrogenated substance (C) in the thermoplastic elastomer composition is W. 0 (mass%), gel content W 1 (As mass%) Ratio W 1 / W 0 A method for producing a thermoplastic elastomer composition, characterized in that the value of is 0.01 to 0.

70.

6. An instrument panel surface comprising the thermoplastic elastomer composition described in claim 1.

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