Thermoplastic elastomer composition

A thermoplastic elastomer composition comprising:

• a composition obtained by dynamically heat-treating, in the presence of an organic peroxide, a mixture consisting of:
• (I) a crystalline polyolefin resin (A) in an amount of 10 to 50 parts by weight,
• (II) an olefin rubber (B) in an amount of 20 to 60 parts by weight,
• (III) a styrene block copolymer (C2) in an amount of 5 to 25 parts by weight, said copolymer (C2) comprising a polymer block (c-1) of styrene or its derivative and a polymer or copolymer block (c-2-2) which is an isoprene polymer block, a butadiene polymer block or an isoprene-butadiene copolymer block, wherein the total content of 1,2-bonds and 3,4-bonds in an isoprene polymer portion is not more than 30%, and not less than 97% of unsaturated bonds are hydrogenated,
• (IV) a softener (D) in an amount of 5 to 40 parts by weight,
• the total amount of said components (A), (B), (C2) and (D) being 100 parts by weight,
• (V) optionally, a peroxide non-crosslinked hydrocarbon rubber (E) in an amount of 1 to 20 parts by weight based on 100 parts by weight of the total amount of the crystalline polyolefin resin (A), the olefin rubber (B), the styrene block copolymer (C2), the softener (D) and the peroxide non-crosslinked hydrocarbon rubber (E), and
• (VI) optionally, at least one additive selected from the group consisting of heat stabilizer, antistatic agent, weathering stabilizer, anti-aging agent, filler, colorant and lubricant, and having a gel content of not less than 97%.