PREPARATION OF LLDPE HAVING CONTROLLED XYLENE SOLUBLES OR HEXANE EXTRACTABLES

摘要

Disclosed is a method for making LLDPE grades having different xylene solubles or hexane extractables with the same Ziegler-Natta catalyst by varying the amount of alkylaluminum used for polymerization. The method comprises copolymerizing ethylene with a C3-10 α-olefin in the presence of a Ziegler-Natta catalyst, an alkylaluminum, and an electron donor; determining the dependency of the xylene solubles or hexane extractables on the alkylaluminum/electron donor ratio; and adjusting the alkylaluminum/electron donor ratio to achieve a desired xylene solubles or hexane extractables.