Polyethylene resins
AssigneeExxonMobil Chemical Patents Inc.
InventorsDavid Bruce Barry, Gary M. Diamond, Hitesh A. Fruitwala, Shih-May Christine Ong, Chunming Wang
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Abstract
The invention provides ethylene/α-olefin copolymers exhibiting improved environmental stress cracking resistance properties, and methods for the production of the copolymers in a single reactor by means of a bimetallic catalyst including a Ziegler component and a metallocene component.
Claims17
An ethylene/α-olefin copolymer possessing a Bent Strip ESCR, T50, of at least 175 hours, wherein the copolymer has a bimodal molecular weight distribution and comprises at least a high molecular weight (HMW) polymer component and at least a low molecular weight (LMW) polymer component which has a lower weight average molecular weight and a higher density than the HMW polymer component, the copolymer prepared in a single reactor with a bimetallic polymerization catalyst comprising a Ziegler component and a metallocene component;
- wherein the HMW polymer component has a molecular weight distribution, Mw/Mn, of from 3 to 6.
An ethylene/α-olefin copolymer possessing a Bent Strip ESCR, T50, of at least 175 hours and having a bimodal molecular weight distribution and a density of at least 0.953 g/cm3, the copolymer comprising at least a HMW polymer component and at least a LMW polymer component having a lower weight average molecular weight than the HMW polymer component, the HMW polymer component comprising at least 30 mol % of the total α-olefin present in the copolymer, the copolymer prepared in a single reactor;
- wherein the HMW polymer component has a density within the range of from 0.930 to 0.950 g/cm3, and the LMW polymer component has a density of at least 0.955 g/cm3 wherein the HMW polymer component has a molecular weight distribution Mw/Mn of from 3 to 6.
Dependencies are inferred from the claim text.