CATALYSTS AND METHODS OF CONTROLLING LONG CHAIN BRANCHING IN POLYOLEFINS

摘要

The present disclosure relates to catalysts comprising two heterogeneous chromium catalysts for the polymerization of olefins are provided herein. The catalysts, as well as related compositions and methods using the same, may be used to for the production of polyolefins, including for the production of bimodal molecular weight distribution polyolefins, e.g., polyethylene and copolymers of ethylene and 1-hexene.

主权项

1. A composition comprising:
(A) a first catalyst comprising from 0.25-2 wt. % chromium deposited on a first solid oxide component, wherein the first catalyst has a pore volume from 1.0-3.5 mL/g and a surface area from 250-900 m2/g; and (B) a second catalyst comprising from about 0.25-2 wt. % chromium deposited on a second solid oxide component, wherein the second catalyst has a pore volume from 1.0-2.5 mL solid/g and a surface area from 400-1000 m2/g; wherein the first and second catalysts are present a weight ratio from 1:9-9:1, provided that the first catalyst and second catalyst are not the same.