A new strategy to increase comonomer incorporation in LLDPE synthesis using Ziegler-Natta catalysts

Abstract

Effect of FeCl3 and FeCl3/SiCl4-doping on the performance of MgCl2(ethoxide type)/TiCl4/TEAL catalytic system was evaluated in the linear low density polyethylene (LLDPE) synthesis using 1-hexene as the comonomer. Results revealed that FeCl3/SiCl4 modified catalytic system has better performance in terms of catalyst activity and comonomer incorporation when compared with unmodified catalyst or the catalytic system in the presence of FeCl3 alone. In fact, the introduction of FeCl3 doper, in its optimum amount of 10 wt. %, together with SiCl4 induced better catalytic performance with 212 and 90 % increase in catalyst activity and 1-hexene incorporation, respectively. Copolymers characterization showed increased bulk density together with decreased crystallinity and Tm in the polymers from modified catalysts. Overall results showed that, new catalytic system represented in this work, is a good candidate for large scale LLDPE production with high comonomer amount.