| 摘要 |
A film, sheet, or tube having an excellent low-temperature shrinkage suitable for use as, for example, a heat shrinkable label is disclosed. This film, sheet, or tube contains, as a base polymer, a block copolymer of an aromatic vinyl hydrocarbon polymer block and a polymer block composed mainly of a conjugated diene having the following structure: -(a) (AB)n n = 2-10 -(b) A(BA)n n = 2-10 -(c) B(AB)n n = 2-10 -(d) [(BA)n]m+2X n = 2-10 and m = 1-10 -(e) [(AB)n]m+2X n = 2-10 and m = 1-10 -(f) [(BA)nB]m+2X n = 1-10 and m = 1-10, or -(g) [(AB)nA]m+2X n = 1-10 and m = 1-10 - wherein A is an aromatic vinyl hydrocarbon polymer block having a number-average molecular weight of 10,000 through 70,000, B is a polymer block composed mainly of a conjugated diene, and X is a residual group of a coupling agent or a polyfunctional initiator such as an organo polylithium compound, the weight ratio of the aromatic vinyl hydrocarbon to the conjugated diene being 60:40 through 95:5. |
