Transition metal catalysts have high catalystic activity and molecular tailoring properties in the field of olefin polymerization.Design and assembley of olefin polymers can be obtained at molecular level by tailoring the microstructure of these catalysts and controlling the polymerization environment such as temperature or pressure.New polymers with novel properties could be obtained

so these catalysts have been attracted much attention in recent years.In the present review

the recent synthesis and support of these catalysts

as well as aqueous and living polymerization are reported.