Polyethylene having improved branching degree distribution
AssigneeJapan Polyehtylene Corporation
InventorsYuuichi Kuzuba, Takashi Monoi, Satoshi Kanazawa, Kouichi Ogawa, Takaaki Hattori, Keiichi Yoshimoto
Life of this patent
Estimating the term…
Abstract
The polyethylene of the invention is polymerized using a chromium catalyst, and has a weight average molecular weight (Mw) of 30,000 or more at the maximum value in a branching degree distribution curve that shows a molecular weight dependency of short chain branches having 4 or more carbon atoms.
Claims14
A polyethylene, having a weight average molecular weight (Mw) of 30,000 or more at a maximum value in a branching degree distribution curve that shows a molecular weight dependency of short chain branches having 4 or more carbon atoms, wherein the polyethylene is polymerized with a chromium catalyst.
A method for producing polyethylene having a weight average molecular weight (Mw) of 30,000 or more at a maximum value in a branching degree distribution curve that shows a molecular weight dependency of short chain branches having 4 or more carbon atoms,
- the method comprising polymerizing the polyethylene with a chromium catalyst obtained by a process comprising:
- calcining and activating an inorganic oxide support having a chromium compound supported thereon at a temperature of from 400 to 900° C. in a non-reducing atmosphere to convert at least a part of chromium atoms into hexavalent atoms;
- supporting an organoaluminum compound in an inert hydrocarbon solvent;
- removing the solvent;
- and
- drying.
Dependencies are inferred from the claim text.