| abstract |
PROBLEM TO BE SOLVED: To provide a polyethylene polymer suitably used for a pipe and a joint thereof having excellent rigidity, impact resistance and creep characteristics. SOLUTION: A polyethylene copolymer comprising ethylene satisfying the following (A), (B) and (C) and an α-olefin having 3 to 12 carbon atoms. (A) MI is 0.04 or more 0.18 g / 10 minutes, (B) density 950-957 kg / Cm 3 , (C) Thai molecule formation fraction (P) and density (D) Satisfies the following relationship. When 950 ≦ D <953, P ≧ 16.0% When 953 ≦ D ≦ 957, P ≧ (969.0−D)% |