Chevron Phillips Chemical Company LP

Jeff F Greco

Qing R Yang

Max P McDaniel

Youlu Yu

Tony R Crain

Gary L Glass

Mark L Hlavinka

Vivek Rohatgi

Jim B Askew

Disclosed herein are ethylene-based polymers having a melt index less than 50 g/10 min, a ratio of Mw/Mn from 4 to 20, a density from 0.90 to 0.945 g/cm, and a substantially constant short chain branch distribution. These polymers can be produced using a dual catalyst system containing a boron bridged metallocene compound with a cyclopentadienyl group and an indenyl group, and a single atom bridged metallocene compound with a fluorenyl group.

Dual catalyst systems for producing polymers with a broad molecular weight distribution and a uniform short chain branch distribution

Methods for controlling the die swell of an olefin polymer produced using a dual catalyst system are disclosed. The die swell of the olefin polymer can be increased or decreased as a function of the catalyst weight ratio and the reactant molar ratio used during the olefin polymerization process.

Methods for controlling die swell in dual catalyst olefin polymerization systems

Disclosed herein are ethylene-based polymers generally characterized by a density greater than 0.954 g/cm, high load melt index ranging from 10 to 45 g/10 min, a ratio of high load melt index to melt index ranging from 175 to 600, a rheological slope parameter ranging from 0.15 to 0.30, and an ESCR in 10% igepal exceeding 800 hours. These polymers have the beneficial processability and die swell features of chromium-based resins, but with improved stiffness and stress crack resistance, and can be used in blow molding and other end-use applications.

Polymers with improved ESCR for blow molding applications

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Tulsa, OK, United States of America

Jeff F Greco