Thesis (M.Eng.)--Chulalongkorn University, 2012

The improvement of Ziegler-Natta catalyst activity can be achieve by adjusting the related factors. This research was aimed to investigate the effects of titanium precursors, butylchloride and cocatalyst on the ethylene polymerization activity. The amount of precursors was varied, and then polymerized at 80 0C for 2 h. The results showed that the decrease of catalytic activity was observed when the amount of titanium (IV) alkoxide was increased. Inversely, an increase of butylchloride amount resulted in an increase of catalytic activity Moreover, the effects of types and amount of cocatalyst were also investigated. The obvious increase of catalytic activity was obtained when the amount of cocatalyst was increased and the cocatalyst type was TEA. In addition, the obtained activity from butylchloride per magnesium ratio of 2.5 was similar to the usage of TEA as cocatalyst and a mole ratio per titanium of 5. The external morphology of the obtained polymers was amorphous as the catalyst morphology. However, the molecular weight and molecular weight distribution were narrower when the TEA having molar ratio per titanium of 5 was used.