Using alkylaluminium activators to tailor short chain branching distributions of ethylene/1-hexene copolymers produced with in-situ supported metallocene catalysts

Copolymerizations of ethylene and 1-hexene were carried out with an in-situ supported metallocene catalyst. Copolymers were produced with different al kyl-aluminium activators and the effect on molecular weight distribution (M WD) and short chain branching distribution (SCBD) was examined. It was foun d that different activator types produce polymer with unimodal and narrow M WDs but with very different SCBDs. Each activator exhibits unique comonomer incorporation characteristics which can produce bimodal SCBDs with the use of a single activator. Therefore, by using individual and mixed activator systems, it is possible to control the SCBDs of the resulting copolymers wh ile maintaining narrow MWDs.