Synthesis of novel Ziegler Natta catalyst in the presence of internal promoter and electron donors for ethylene and ethylene/1-hexene polymerization

In this study, the simultaneous effect of cyclohexyl chloride (CHC) as a high-performance promoter and different electron donors (ED) on ethylene polymerization was studied. The polymerization reactions were carried out using Mg (OEt)(2)/ TiCl4/ TEAl Ziegler-Natta catalyst system. The results showed that CHC and ED, like methanol and diethyl ether (DEE), had a high impact on ethylene polymerization and copolymerization with 1-hexene. The catalyst activity was increased in the optimum ratio of CHC and ED up to 40% and 212.5% for methanol and DEE, respectively, than the donor-free system. The synthesized catalysts and polyethylene powder were characterized by scanning electron microscopy (SEM). The results exhibited the positive effects of EDs on catalysts morphology in the presence of CHC and ED. Through using methanol, an increase in the catalyst's porosity led to increased activity, while DEE creates cracks on the surface catalyst particles and incremented the catalyst activity by increasing fragmentation phenomena. The EDs had direct effects on melt flow index (MFI) as well as flow rate ratio (FRR) and also improved wax and fine (<63 mu m) content in produced polyethylene. The particle size distribution (PSD) results indicated that polyethylene powder had a larger particle size and favorable operating properties in the presence of DEE and methanol. Thermal analysis of different synthesized polyethylene demonstrated that polyethylene's crystallinity and melting point did not change with EDs and CHC.

Automated summary

This study investigated the simultaneous effect of cyclohexyl chloride (CHC) and various electron donors (ED) on ethylene polymerization, elucidating their significant impact on catalyst activity and polymer product properties. The use of methanol and diethyl ether (DEE) as EDs led to increased catalyst activity and improved characteristics of the produced polyethylene. The morphology of the catalysts was positively affected by the presence of CHC and ED, with differences observed in the influence of methanol and DEE on catalyst porosity and fragmentation phenomena.