Block Copolymer Compositions

A hydrogenated block copolymer comprising block copolymer components (a) and (b), wherein

• block copolymer component (a) is a selectively hydrogenated block copolymer comprising one or more structures A-B-A, (A-B-A)nX, A-(B-A)n, and (A-B)nX;
• block copolymer component (b) is a selectively hydrogenated block copolymer comprising one or more structures C-D, D-C-D, and (D-C-)nX;
• and
• wherein “n” is 1-30, and “X” is a residue of a coupling agent;
• wherein before hydrogenation,
• A is a polymer block of a vinyl aromatic monomer, having a peak molecular weight (Mp) of 14-60 kg/mol,
• B is a polymer block comprising 60-100 mol % of one or more conjugated dienes, and 0-40 mol % of a vinyl aromatic monomer;
• C is a polymer block of a vinyl aromatic monomer, having a peak molecular weight of 1-8 kg/mol;
• and
• D is a polymer block comprising 60-100 mol % of one or more conjugated dienes, and 0-40 mol % of a vinyl aromatic monomer;
• wherein after hydrogenation,
• 80 to 100 mol % of the polymerized diene units in the polymer blocks B and D are reduced;
• and
• 0-20 mol % of the polymerized vinyl aromatic monomer units in the polymer blocks A, B, C and D are reduced;
• wherein the vinyl aromatic monomers of the polymer blocks A, B, C and D are independently same or different and the conjugated diene monomers for the polymer blocks B and D are independently same or different;
• wherein the block copolymer component (a) has a peak molecular weight of 100-1,000 kg/mol and the block copolymer component (b) has a peak molecular weight of 6-60 kg/mol;
• and
• wherein the hydrogenated block copolymer has a compression set after 24 hrs. at 70° C. of less than 50%, measured according to ASTM D395, an apparent viscosity measured at 230° C., and a shear rate of 5000/s of <70 Pa·s.