Thermoplastic Elastomers of High Vinyl Block Copolymer Compositions

A styrenic block copolymer composition comprising at least one high vinyl block copolymer selected from the group consisting of:

• (i) a block copolymer having the formula:
• (S—B)n-S, (B—S)n-B, or (S—B)n,
• wherein S is a vinyl aromatic polymer block,
• wherein S content in the block copolymer is from 10 to 40 wt %,
• wherein randomized vinyl aromatic repeat unit content is less than 15 wt % based on total vinyl aromatic content,
• wherein B is a conjugated diene polymer block,
• wherein the B block has a vinyl content of more than 85 mol % on a conjugated diene repeat unit basis, including 1,2-vinyl, 3,4-vinyl and vinylcyclopentane (VCP) repeat units,
• wherein n is a value from 1 to 5, and
• wherein the GPC peak molecular weight Mp of the block copolymer relative to polystyrene standards is from 50 to 300 kg/mol;
• (ii) a block copolymer having the formula:
• [(S—B)m-S]n-X, [(B—S)m-B]n-X, [(S—B)m]n-X, or [(B—S)m]n-X,
• wherein S is a vinyl aromatic polymer block,
• wherein S content in the block copolymer is from 10 to 40 wt %,
• wherein randomized vinyl aromatic repeat unit content is less than 15 wt % based on total vinyl aromatic content,
• wherein B is a conjugated diene polymer block,
• wherein the B block has a vinyl content of more than 85 mol % on a conjugated diene repeat unit basis, including 1,2-vinyl, 3,4-vinyl and vinylcyclopentane (VCP) repeat units,
• wherein m is a value from 1 to 3,
• wherein n is a value from 2 to 30,
• wherein X is the residue of a coupling agent, and
• wherein the GPC peak molecular weight Mp of the block copolymer relative to polystyrene standards is from 50 to 480 kg/mol;
• and
• (iii) a block copolymer having the formula:
• (S—B)n-S-f, (B—S)n-B-f, [(S—B)n]-f or [(B—S)n]-f,
• wherein S is a vinyl aromatic polymer block,
• wherein S content in the block copolymer is from 10 to 40 wt %,
• wherein randomized vinyl aromatic repeat unit content is less than 15 wt % based on total vinyl aromatic content,
• wherein B is a conjugated diene polymer block,
• wherein the B block has a vinyl content of more than 85 mol % on a conjugated diene repeat unit basis, including 1,2-vinyl, 3,4-vinyl and vinylcyclopentane (VCP) repeat units,
• wherein n is a value from 1 to 5,
• wherein f is an end group with an —OH or a secondary amine moiety, and
• wherein the GPC peak molecular weight Mp of the block copolymer relative to polystyrene standards is from 50 to 300 kg/mol;
• wherein the block copolymer composition comprises a VCP content of less than 6 wt % on a total conjugated diene basis.