Polyethylene for pipe and joint, and molded body thereof

A polyethylene, which satisfies the following characteristics (1) to (5):

• Characteristic (1):
• a melt flow rate at a temperature of 190° C. and a load of 21.6 kg (HLMFR) is 5 to 20 g/10 minutes,
• Characteristic (2):
• a density (D) is 0.954 to 0.960 g/cm3,
• Characteristic (3):
• a ratio of weight-average molecular weight (Mw) and number-average molecular weight (Mn) (Mw/Mn) measured by gel permeation chromatography (GPC) is 15 to 27,
• Characteristic (4):
• a rupture time at 80° C. and 5 MPa by a full notch creep test (FNCT) is 150 hours or more, and
• Characteristic (5):
• a Charpy impact strength (CIS) measured at −20° C. is 8.5 kJ/m2 or more,
• wherein the polyethylene contains at least 25 to 35% by weight of the following polyethylene component (a) and 75 to 65% by weight of the polyethylene component (b):
• the polyethylene component (a) being a polyethylene which is polymerized using a metallocene catalyst, has an HLMFR of 0.01 to 0.5 g/10 minutes, and has a density of 0.915 to 0.930 g/cm3 and
• the polyethylene component (b) being a polyethylene which is at least one of an ethylene homopolymer and a copolymer of ethylene and an α-olefin, has a melt flow rate (MFR) at a temperature of 190° C. and a load of 2.16 kg of 1 to 10 g/10 minutes, a density of 0.960 to 0.975 g/cm3, and an Mw/Mn of 12 to 25, and
• wherein the polyethylene component (b) is composed of 18 to 30% by weight of a polyethylene component (b-1) and 70 to 82% by weight of a polyethylene component (b-2), the polyethylene component (b-1) has an HLMFR of 0.45 to 4.0 g/10 minutes and a density of 0.935 to 0.955 g/cm3, and the polyethylene component (b-2) has an MFR of 50 to 200 g/10 minutes and a density of 0.960 to 0.975 g/cm3.