| 摘要 |
A polyethylene composition obtainable by polymerizing ethylene and an optional olefin with >/=3 carbon atoms in the presence of a macromonomer, is provided. The macromonomer is a vinyl-terminated ethylene polymer obtainable by polymerizing ethylene and an optional olefin with >/=3 carbon atoms, and the macromonomer has (A) Mn >/= 5,000, and Mw/Mn = 2-5. The polyethylene composition comprises (C) branched polyethylene obtainable by copolymerizing ethylene, the macromonomer and an optional olefin with >/=3 carbon atoms, and the macromonomer. The polyethylene composition has (D) a density of 0.890-0.980 g/cm<3>, (E) Mw = 30,000-10,000,000, (F) Mw/Mn = 2-30, (G) a long chain branch frequency of 0.01-3 per 1,000 C atoms, and (H) a shrinking factor (g' value) of 0.1-0.9 as measured by GPC/intrinsic-viscosity. The polyethylene composition can be in the form of finely divided particles having (P) a powder bulk density of 0.15-0.50 g/cm<3>. |
