| Abstract: | A magnesium/electron donor complex was used as support for the synthesis of a titanium catalyst. By interaction of TiCl4 with MgCl2(THF)2 a highly active and stable catalyst for ethylene polymerization was obtained. The catalytic activity of the MgCl2(THF)2/TiCl4/AlEt2Cl system in the polymerization of ethylene was investigated as a function of Mg/Ti and Al/Ti mole ratios as well as the donor concentration in the system. Some kinetic studies of ethylene polymerization in the presence of this catalyst allowed us to determine the concentration of active centres (ca. 60 mol-% of Ti), rate constants of elementary reactions (kp ≈ 92 dm3/(mol · s)) and kinetic equations. From these results it was possible to find further evidence for the role of the donor ligands in titanium catalysts supported on magnesium dichloride in the presence of Al-alkyls as cocatalysts. |
