| abstract |
(57) [Summary] [Purpose] To provide an ethylene polymer having improved creep life and excellent long-term durability. [Structure] The product L C of the lamella thickness L C defined by the following formula (1) and the tie molecular fraction f t1 defined by the following formula (2) An ethylene-based polymer having xf t1 of 15 or more is used. L C = L × C (1) (L C : lamella thickness, L: long period, C: crystallinity measured by DSC) f t1 = (σ B −σ w ) / (σ t −σ w ). (2) (f t1 : Thai molecular fraction, σ B : tensile breaking stress at 77 K, σ w = 8 GPa, σ t = 300 GPa) |