Ziegler-Natta catalyst with high activity and good hydrogen response
Keywords:Ziegler-Natta catalyst, Polyethylene, Magnesium chloride, Hydrogen response
AbstractZiegler-Natta catalysts were prepared from chemical reaction route comprising of steps of 1) magnesium complex formation between butyloctyl magnesium and 2-ethyl-1-hexanol, 2) MgCl2 support preparation from the reaction between the magnesium complex and TiCl4 as chlorinating agent and 3) titanation with TiCl4. The catalysts were used for ethylene polymerization using triethylaluminum as a cocatalyst. Effects influencing properties of catalysts and polymerization performance were investigated: triethylaluminum/Mg molar ratio, Ti/Mg molar ratio, addition of electron donor and aging step. Results show that addition of ethylbenzoate as an electron donor resulted in decreased catalytic activity. However it was found that catalytic stability under high pressure was increased, as revealed by higher activity balance. Activity of the catalyst can be improved by performing aging step. High density polyethylene was produced in slurry process.
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