Polymerization of olefins in the presence of chromium-containing catalysts
AssigneeThe Dow Chemical Company
InventorsFred L. Vance, Jr., Rafael E. Guerra, Christopher P. Christenson
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Abstract
Olefins are polymerized in the presence of chromium-containing catalysts which have been improved by depositing the chromium onto the inorganic oxide support in the vapor phase rather than as an inorganic or organic compound. The resulting polymers exhibit a higher molecular weight as compared to those polymers prepared in the presence of such chromium-containing catalysts prepared in the conventional manner.
Claims18
In a process for polymerizing one or more a-olefins in the presence of an inorganic oxide supported chromium-containing catalyst wherein said catalyst has been prepared by contacting said inorganic oxide support with a chromium-containing compound followed by activation of an oxidizing atmosphere at an elevated temperature for a time sufficient to activate the catalyst;
- the improvement which comprises employing as catalyst one prepared by contacting said inorganic oxide support with a metallic composition containing zero valent chromium in the vapor state instead of compounds of such metals and wherein the polymerization is also conducted in the presence of a metal alkyl compound.
Dependencies are inferred from the claim text.