Influence of SiO2 specifications on Polyethylene microstructure from the (SiO2/MgCl2/TEOS/TiCl4/AlEt3) catalyst system

The properties of olefin polymers greatly depend on the microstructure of polyolefin, e.g. molecular weight, molecular weight distribution and chain branching content and itsdistribution [1-3]. Despite of the wide use of supported SiO2- MgCl2 based Ziegler-Natta catalysts in the olefin polymerization industry [4], questions concerning the role of the SiO2 support specification on molecular properties have not found a satisfactory answer [5]. In this paper, we willconcentrate on understanding the role of the physical properties of the catalyst support particularly the role of porosity on the molecular properties in SiO2-MgCl2 Ziegler- Natta catalyst