Dana Shoken

Non-metallocene systems are currently playing a key role in the quest for highly efficient olefin polymerization catalysts. Most of the research on non-metallocene chemistry is done on catalysts bearing two ancillary ligands but less focus is given to catalysts bearing mono ancillary ligands. One of the known monodentate catalyst is monocyclopentadienyl titanium trichloride (CpTiCl₃) which is found good catalyst for the polymerization of syndiotactic polystyrene in the combination of the co-catalyst (MAO) unlike most of the bidentate non-metallocene catalysts. To increase our knowledge on the behavior of mono catalysts we wish to present in this work our studies of non-metallocene titanium complexes bearing mono lmidazolin-2-iminato ligand.  

  This work presents the catalytic activity of the known catalyst 1,3-bis-(2,6-diisopropylphenyl)imidazoline-2-iminato titanium trichloride (DippTiCl₃) toward the polymerization of ethylene, propylene, styrene and ethylene-styrene co-polymerization, as well as the catalytic activity of the methylated catalysts 1,3-bis-(2,6-diisopropylphenyl)imidazoline-2-iminato titanium dimethyl chloride (DippTiClMe₂) and 1,3-bis-(2,6-diisopropylphenyl)imidazoline-2-iminato titanium trimethyl (DippTiMe₃) towards ethylene and propylene polymerization. The novel 1, 3-bis-(2,4,6-trimethylphenyl)imidazoline-2-iminato titanium trichloride (MesTiCl₃) catalyst shows good catalytic activity toward the polymerization of ethylene at a very low ratio of co-catalyst (MAO) to catalyst. The effect of using different co-catalysts on the catalytic activity of DippTiCl₃, DippTiClMe₂, DippTiMe₃ and MesTiCl₃ was studied.