Patent ID: 7230054
Filing Date: 2007-06-12
Classification: C08F,C08L

Abstract:
1. A resin comprising a relatively high-density, low-molecular-weight polyethylene component and a relatively low-density, high-molecular-weight ethylene copolymer component, wherein the resin is produced in first and second slurry-tank reactors operating in parallel at a temperature within the range of about 60° C. to about 120° C., wherein ethylene polymerizes in the first reactor in the presence of a Ziegler-Natta catalyst and an optional 1-olefin comonomer to provide the high-density polyethylene component, and wherein additional ethylene polymerizes in the second reactor in the presence of a silane-modified Ziegler-Natta catalyst and a 1-olefin comonomer to provide the low-density ethylene copolymer component, said high and low-density components being blended to provide the resin, wherein the rheological polydispersity of the high-density component exceeds that of the resin.