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Ansa-Cyclohexyl-bis(4,5,6,7-tertrahydro-1-indenyl) zirconium dichloride (5) was used as catalyst for propylene and ethylene polymerization together with methyl aluminoxane (MAO) as the cocatalyst.Isotactic polypropylene (PP) was obtained with the highest activity of 6.37×107g PP (molZr)-1h-1. The mesomeso (mmmmm) pentads sequence content of PP was determined by 13C NMR spectroscopy. The dependence of the microstructure on the reaction temperature and the Al/Zr molar ratio was examined and the catalytic activity of complex 5 was compared with that of the similar ansa-zirconocene 3. The high activity of the new zirconocene 5 for propylene isospectic polymerization at high temperature (60 ℃) is the result of its unique bridged-group structure. Complex 5/MAO displays also high catalytic activity of 0.46×106 to 9.87×106gPE(molZr)-1h-1 in the homo-polymerization of ethylene. The visometric molecular weight of PE ranges from linear polyethylene (LPE).