| 摘要 |
<p>Provided is a composition for a stretchable film, which achieves a high-level balance between a high elastic modulus and a small permanent set, and can be formed into a stretchable film with satisfactory formability. A composition for a stretchable film comprises a block copolymer composition containing a block copolymer A represented by the following general formula (A) and a block copolymer B represented by the following general formula (B), and a tackifier resin:
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒAr1 a -D a -Ar2 a €ƒ€ƒ€ƒ€ƒ€ƒ(A)
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ(Ar b -D b ) n -X€ƒ€ƒ€ƒ€ƒ€ƒ(B),
in the general formulas (A) and (B), Ar1 a and Ar b each represent an aromatic vinyl polymer block having a weight average molecular weight of 6,000 to 20,000; Ar2 a represents an aromatic vinyl polymer block having a weight average molecular weight of 40,000 to 400,000; D a and D b each represent a conjugated diene polymer block having a vinyl bond content of 1 mol% to 20 mol%; X represents a single bond or a residue of a coupling agent; and n represents an integer of 2 or greater.</p> |
