Process for production of thermoplatic elastomer composition

A thermoplastic elastomer composition which is obtained by, in a single-stage step, melting and kneading a mixture under heating to be dynamically crosslinked, wherein said mixture contains:

• (i) a hydrogenated block copolymer (a1) with a number average molecular weight of 200,000 or above which is obtained by hydrogenating a block copolymer that has at least one polymer block A1 comprising mainly a vinyl aromatic compound and at least one polymer block B1 comprising mainly a conjugate diene compound, and a non-hydrogenated block copolymer (a2) which has at least one polymer block A2 comprising mainly a vinyl aromatic compound and at least one polymer block B2 comprising mainly a conjugate diene compound, at a mass ratio of the hydrogenated block copolymer (a1):
• the non-hydrogenated block copolymer (a2)=85:15 to 100:0;
• (ii) a non-aromatic rubber softening agent (b) at a ratio of 50 to 250 mass parts per 100 mass parts of the total of the hydrogenated block copolymer (a1) and the non-hydrogenated block copolymer (a2);
• (iii) a peroxide-crosslinkable olefin resin (c) with a density of 0.94 g/cm3 or above at a ratio of 2.5 to 50 mass parts per 100 mass parts of the total of the hydrogenated block copolymer (a1) and non-hydrogenated block copolymer (a2);
• (iv) a peroxide-decomposable olefin resin (d) at the rate of 0.5 to 10 times by mass the mixture amount of the peroxide-crosslinkable olefin resin (c);
• and
• (v) an organic peroxide (e) and a crosslinking aid (f).

A thermoplastic elastomer composition, which is obtained by, in an arbitrary step that contains a single stage step, melting and kneading a mixture under heating to be dynamically crosslinked, wherein said mixture contains:

• (i) a hydrogenated block copolymer (a1) with a number average molecular weight of 200,000 or above which is obtained by hydrogenating a block copolymer that has at least one polymer block A1 comprising mainly a vinyl aromatic compound and at least one polymer block B1 comprising mainly a conjugate diene compound, and a non-hydrogenated block copolymer (a2) which has at least one polymer block A2 comprising mainly a vinyl aromatic compound and at least one polymer block B2 comprising mainly a conjugate diene compound, at a mass ratio of the hydrogenated block copolymer (a1):
• the non-hydrogenated block copolymer (a2)=85:15 to 99:1;
• (ii) a non-aromatic rubber softening agent (b) at a ratio of 50 to 250 mass parts per 100 mass parts of the total of the hydrogenated block copolymer (a1) and the non-hydrogenated block copolymer (a2);
• (iii) a peroxide-crosslinkable olefin resin (c) with a density of 0.94 g/cm3 or above at a ratio of 2.5 to 50 mass parts per 100 mass parts of the total of the hydrogenated block copolymer (a1) and non-hydrogenated block copolymer (a2);
• (iv) a peroxide-decomposable olefin resin (d) at the rate of 0.5 to 10 times by mass the mixture amount of the peroxide-crosslinkable olefin resin (c);
• and
• (v) an organic peroxide (e) and a crosslinking aid (f).