Single catalyst low, medium and high density polyethylenes

Details Single catalyst low, medium and high density polyethylenes Single catalyst low, medium and high density polyethylenes

2006-07-18

2006-07-18

Teskin, Fred (Department: 1713)

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

Polymers from only ethylenic monomers or processes of...

C526S087000, C526S160000, C526S170000, C526S901000, C526S905000

Reexamination Certificate

active

07078467

ABSTRACT:
A method of polymerizing olefins comprising combining in one embodiment ethylene and optionally one or more α-olefins with a catalyst composition in a continuous polymerization reactor at a pressure of less than 10,000 kPa; wherein the catalyst composition comprises a hafnocene; and isolating a polyethylene having a density in the range of from 0.930 to 0.975 g/cm3. Also provided is a method of transitioning a continuous polymerization reactor from production of a low density polyethylene to a medium or high density polyethylene. Also provided is a medium to high density polyethylene suitable for injection or rotomolding applications. Also provided is a single catalyst composition suitable for such needs.

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