Thermoplastic elastomer composition for powder molding, powder and molded article thereof

A two-layer molded article obtained by laminating on one surface of a molded article a foamed layer, wherein said molded article is obtained by powder-molding a powder of a thermoplastic elastomer composition produced by a strand cut method, die face cut method or solvent treating method, the thermoplastic elastomer composition comprising 100 parts by weight of the following component (A) and 10 to 1000 parts by weight of the following component (B), wherein the composition has a complex dynamic viscosity η*(1) at 250° C. of 1.5×105 poise or less and a Newtonian viscosity index n of 0.67 or less:

• (A):
• a polyolefin-based resin, and
• (B):
• a hydrogenated diene-based copolymer satisfying all of the following conditions {circle around (1)} to {circle around (7)},
• {circle around (1)}:
• the hydrogenated diene-based copolymer comprises the following structural units (a) and (b):
• (a):
• a vinyl aromatic compound polymer block,
• (b):
• at least one kind of block selected from the following (b1), (b2) and (b3):
• (b1):
• a block obtained by hydrogenation of a random copolymer block composed of a vinyl aromatic compound and a conjugated diene,
• (b2):
• a block obtained by hydrogenation of a block in the form of taper composed of a vinyl aromatic compound and a conjugated diene in which the amount of the vinyl aromatic compound increases gradually,
• (b3);
• a block obtained by hydrogenation of a conjugated diene polymer block,
• {circle around (2)}:
• the total content (T:
• percentage) of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer from 10 to 18% by weight,
• {circle around (3)}:
• the ratio (S:
• percentage) of the content of the vinyl aromatic compound unit of (a) in {circle around (1)} to the total content of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer is 3% or more,
• {circle around (4)}:
• the ratio (V:
• percentage) of the number of hydrogenated conjugated diene units having a side chain of two or more carbon atoms to the total number of hydrogenated conjugated diene units in the hydrogenated diene-based copolymer is over 60%,
• {circle around (5)}:
• (T) in {circle around (2)}, (S) in {circle around (3)} and (V) in {circle around (4)} in the hydrogenated diene-based copolymer satisfy the relation represented by the following formula (1):
• V≦0.375×S+1.25×T+40 (1)
• {circle around (6)}:
• 80% or more of double bonds in conjugated diene units in the hydrogenated diene-based copolymer are hydrogenated, and
• {circle around (7)}:
• the number-average molecular weight of the hydrogenated diene-based copolymer is from 50000 to 400000, and
• said foamed layer is prepared from a thermoplastic elastomer composition containing 100 parts by weight of the following component (G) and 10 to 1000 parts by weight of the following component (H);
• (G):
• a polyolefin-based resin,
• (H):
• a rubber-like polymer wherein in tan δ-temperature-dependent curve obtained by measuring solid viscoelasticity of a composition prepared by kneading with (G), a novel single tan δ peak is given at a temperature different from both of the tan δ peak temperature of (G) and the tan δ peak temperature of (H), in a temperature range from −70 to 30° C.

A multi-layer molded article obtained by laminating a thermoplastic resin core material on one surface of a molded article obtained by powder molding a powder of a thermoplastic elastomer composition obtained by mechanically pulverizing a thermoplastic elastomer composition comprising 100 parts by weight of the following component (A) and 10 to 1000 parts by weight of the following component (B), wherein the composition has a complex dynamic viscosity η*(1) at 250° C. of 1.5×105 poise or less and a Newtonian viscosity index n of 0.67 or less:

• (A):
• a polyolefin-based resin, and
• (B):
• a hydrogenated diene-based copolymer satisfying all of the following conditions {circle around (1)} to {circle around (7)},
• {circle around (1)}:
• the hydrogenated diene-based copolymer comprises the following structural units (a) and (b):
• (a):
• a vinyl aromatic compound polymer block,
• (b):
• at least one kind of block selected from the following (b1), (b2) and (b3):
• (b1):
• a block obtained by hydrogenation of a random copolymer block composed of a vinyl aromatic compound and a conjugated diene,
• (b2):
• a block obtained by hydrogenation of a block in the form of taper composed of a vinyl aromatic compound and a conjugated diene in which the amount of the vinyl aromatic compound increases gradually,
• (b3):
• a block obtained by hydrogenation of a conjugated diene polymer block,
• {circle around (2)}:
• the total content (T:
• percentage) of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer from 10 to 18% by weight,
• {circle around (3)}:
• the ratio (S:
• percentage) of the content of the vinyl aromatic compound unit of (a) in {circle around (1)} to the total content of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer is 3% or more,
• {circle around (4)}:
• the ratio (V:
• percentage) of the number of hydrogenated conjugated diene units having a side chain of two or more carbon atoms to the total number of hydrogenated conjugated diene units in the hydrogenated diene-based copolymer is over 60%,
• {circle around (5)}:
• (T) in {circle around (2)}, (S) in {circle around (3)} and (V) in {circle around (4)} in the hydrogenated diene-based copolymer satisfy the relation represented by the following formula (1):
• V≦0.375×S+1.25×T+40 (1)
• {circle around (6)}:
• 80% or more of double bonds in conjugated diene units in the hydrogenated diene-based copolymer are hydrogenated, and
• {circle around (7)}:
• the number-average molecular weight of the hydrogenated diene-based copolymer is from 50000 to 400000.

A multi-layer molded article obtained by laminating a thermoplastic resin core material on one surface of a molded article obtained by powder-molding a powder of a thermoplastic elastomer composition produced by a strand cut method, die face cut method or a solvent treating method, the thermoplastic elastomer composition comprising 100 parts by weight of the following component (A) and 10 to 1000 parts by weight of the following component (B), wherein the composition has a complex dynamic viscosity η*(1) at 250° C. of 1.5×105 poise or less and a Newtonian viscosity index n of 0.67 or less:

• (A):
• a polyolefin-based resin, and
• (B):
• a hydrogenated diene-based copolymer satisfying all of the following conditions {circle around (1)} to {circle around (7)},
• {circle around (1)}:
• the hydrogenated diene-based copolymer comprises the following structural units (a) and (b):
• (a):
• a vinyl aromatic compound polymer block,
• (b):
• at least one kind of block selected from the following (b1), (b2) and (b3):
• (b1):
• a block obtained by hydrogenation of a random copolymer block composed of a vinyl aromatic compound and a conjugated diene,
• (b2):
• a block obtained by hydrogenation of a block in the form of taper composed of a vinyl aromatic compound and a conjugated diene in which the amount of the vinyl aromatic compound increases gradually,
• (b3):
• a block obtained by hydrogenation of a conjugated diene polymer block,
• {circle around (2)}:
• the total content (T:
• percentage) of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer from 10 to 18% by weight,
• {circle around (3)}:
• the ratio (S:
• percentage) of the content of the vinyl aromatic compound unit of (a) in {circle around (1)} to the total content of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer is 3% or more,
• {circle around (4)}:
• the ratio (V:
• percentage) of the number of hydrogenated conjugated diene units having a side chain of two or more carbon atoms to the total number of hydrogenated conjugated diene units in the hydrogenated diene-based copolymer is over 60%,
• {circle around (5)}:
• (T) in {circle around (2)}, (S) in {circle around (3)} and (V) in {circle around (4)} in the hydrogenated diene-based copolymer satisfy the relation represented by the following formula (1):
• V≦0.375×S+1.25×T+40 (1)
• {circle around (6)}:
• 80% or more of double bonds in conjugated diene units in the hydrogenated diene-based copolymer are hydrogenated, and
• {circle around (7)}:
• the number-average molecular weight of the hydrogenated diene-based copolymer is from 50000 to 400000.

A method for producing a multi-layer molded article, which comprises feeding a thermoplastic resin melt on one surface of a molded article arid pressing, wherein said molded article is obtained by powder molding a powder of a thermoplastic elastomer composition obtained by mechanically pulverizing a thermoplastic elastomer composition comprising 100 parts by weight of the following component (A) and 10 to 1000 parts by weight of the following component (B), wherein the composition has a complex dynamic viscosity η*(1) at 250° C. of 1.5×105 poise or less and a Newtonian viscosity index n of 0.67 or less:

• (A):
• a polyolefin-based resin, and
• (B):
• a hydrogenated diene-based copolymer satisfying all of the following conditions {circle around (1)} to {circle around (7)},
• {circle around (1)}:
• the hydrogenated diene-based copolymer comprises the following structural units (a) and (b):
• (a):
• a vinyl aromatic compound polymer block,
• (b):
• at least one kind of block selected from the following (b1), (b2) and (b3):
• (b1):
• a block obtained by hydrogenation of a random copolymer block composed of a vinyl aromatic compound and a conjugated diene,
• (b2):
• a block obtained by hydrogenation of a block in the form of taper composed of a vinyl aromatic compound and a conjugated diene in which the amount of the vinyl aromatic compound increases gradually,
• (b3):
• a block obtained by hydrogenation of a conjugated diene polymer block,
• {circle around (2)}:
• the total content (T:
• percentage) of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer from 10 to 18% by weight,
• {circle around (3)}:
• the ratio (S:
• percentage) of the content of the vinyl aromatic compound unit of (a) in {circle around (1)} to the total content of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer is 3% or more,
• {circle around (4)}:
• the ratio (V:
• percentage) of the number of hydrogenated conjugated diene units having a side chain of two or more carbon atoms to the total number of hydrogenated conjugated diene units in the hydrogenated diene-based copolymer is over 60%,
• {circle around (5)}:
• (T) in {circle around (2)}, (S) in {circle around (3)} and (V) in {circle around (4)} in the hydrogenated diene-based copolymer satisfy the relation represented by the following formula (1):
• V≦0.375×S+1.25×T+40 (1)
• {circle around (6)}:
• 80% or more of double bonds in conjugated diene units in the hydrogenated diene-based copolymer are hydrogenated, and
• {circle around (7)}:
• the number-average molecular weight of the hydrogenated diene-based copolymer is from 50000 to 400000.

A method for producing a multi-layer molded article, which comprises feeding a thermoplastic resin inch on one surface of a molded article and pressing, wherein said molded article is obtained by powder molding a powder of a thermoplastic elastomer composition for powder molding produced by a strand cut method, die face cut method or solvent treating method, the thermoplastic elastomer composition comprising 100 parts by weight of the following component (A) and 10 to 1000 parts by weight of the following component (B), wherein the composition has a complex dynamic viscosity η*(1) at 250° C. of 1.5×105 poise or less and a Newtonian viscosity index n of 0.67 or less:

• (A):
• a polyolefin-based resin, and
• (B):
• a hydrogenated diene-based copolymer satisfying all of the following conditions {circle around (1)} to {circle around (7)},
• {circle around (1)}:
• the hydrogenated diene-based copolymer comprises the following structural units (a) and (b):
• (a):
• a vinyl aromatic compound polymer block,
• (b):
• at least one kind of block selected from the following (b1), (b2) and (b3):
• (b1):
• a block obtained by hydrogenation of a random copolymer block composed of a vinyl aromatic compound and a conjugated diene,
• (b2):
• a block obtained by hydrogenation of a block in the form of taper composed of a vinyl aromatic compound and a conjugated diene in which the amount of the vinyl aromatic compound increases gradually,
• (b3):
• a block obtained by hydrogenation of a conjugated diene polymer block,
• {circle around (2)}:
• the total content (T:
• percentage) of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer from 10 to 18% by weight,
• {circle around (3)}:
• the ratio (S:
• percentage) of the content of the vinyl aromatic compound unit of (a) in {circle around (1)} to the total content of vinyl aromatic compound units contained in the hydrogenated diene-based copolymer is 3% or more,
• {circle around (4)}:
• the ratio (V:
• percentage) of the number of hydrogenated conjugated diene units having a side chain of two or more carbon atoms to the total number of hydrogenated conjugated diene units in the hydrogenated diene-based copolymer is over 60%,
• {circle around (5)}:
• (T) in {circle around (2)}, (S) in {circle around (3)} and (V) in {circle around (4)} in the hydrogenated diene-based copolymer satisfy the relation represented by the following formula (1):
• V≦0.375×S+1.25×T+40 (1)
• {circle around (1)}:
• 80% or more of double bonds in conjugated diene units in the hydrogenated diene-based copolymer are hydrogenated, and {circle around (7)}:
• the number-average molecular weight of the hydrogenated diene-based copolymer is from 50000 to 400000.