US Patent 7714074 Polyethylene pipe fitting resins

Polyethylene resin suitable for formation into pipes or pipe fittings having an M15 of from 0.40 to 0.70 g/10 min, and including from 47 to 52 wt % of a low molecular weight polyethylene fraction, and from 48 to 53 wt % of a high molecular weight polyethylene fraction. The high molecular weight polyethylene fraction includes a copolymer of ethylene and 1-hexen or 1-octene, and the resin has a density after granulation and addition of additives of between 957 kg/m3 and 963 kg/m3.