Polymerization of Ethylene using Metallocene and Zeigler Natta catalyst with doped-Nanotitania

Ethylene polymerization was carried out using highly active metallocene catalysts (Cp2ZrCl2 and Cp2TiCl2) in combination with methylalumoxane. Titanium (IV) oxide containing 1% Mn as dopant was used as nanofillers. The influence of filler concentration, reaction temperature and pressure on the catalytic activity and polymer properties was investigated. There was a four-fold increase in the activity of zirconocene catalyst by addition of doped-titania. The morphology indicates that the doped-titania nanoparticles have a nucleus effect on the polymerization and caused a homogeneous PE shell around them. The optimum condition for polymerization was found to be 30°C. The improvement of nanoparticles dispersion in the polyethylene matrix was checked by WAXD. The thermal properties were analyzed using differential scanning calorimetry and thermogravimetric analysis. A detailed investigation on the polymerization of ethylene by Cp2ZrCl2 catalysts was carried out by varying the cyclopentadienyl substituent groups. The activity of catalyst in comparison to the Cp2ZrCl2 was low due to the steric effect from the substituent groups even in the presence of filler.