Patent ID: 8129489

Claim:
An ethylene polymer containing 0.02 to 0.50 mol % of a constitutional unit derived from α-olefin having 6 to 10 carbon atoms, the polymer having a density of 945 to 975 kg/m 3 and satisfying the following requirements [1]-[3] and [2b]-[4b] simultaneously: [1] in cross fractionation chromatography, all the components having a molecular weight of 100,000 or more are eluted at a temperature of 85° C. or higher; [2] the components eluted at a temperature of 80° C. or lower account for up to 5% of all the components eluted in cross fractionation chromatography; [3] the environmental stress cracking resistance (ESCR), as measured at 50° C. according to ASTM-D-1693 is in the range of 600 hr to 800 hr; [2b] the intrinsic viscosity ([η]) as measured in decalin at 135° C. is in the range of 1.6 to 2.8 dL/g; [3b] the flexural modulus, M (MPa), as measured at 23° C. according to ASTM-D-790 satisfies 600 ≦M<1500, and the environmental stress cracking resistance (ESCR), T (hr), as measured at 50° C. according to ASTM-D-1693 and M, satisfy the following equation (Eq-1): T≧−0.8×M+1210 (Eq-1); and [4b] tanδ (loss modulus G″/storage modulus G′) as measured at 190° C. and at an angular frequency of 100 rad/sec using a dynamic viscoelasticity measuring apparatus, is in the range of 0.6 to 0.9.