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Ansa-Cyclohexyl-bis(4,5,6,7-tertrahydro-l-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 6.37×10~7g PP(molZr)~(-1)h~(-1).The meso- meso(mmmmm)pentads sequence content of PP was determined by ~(13)C 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 0.46×10~6 to 9.87×10~6g PE(molZr)~(-1)h~(-1) in the homo-polymerization of ethylene.The visometric molecular weight of PE ranges from 0.97×10~4 to 11.16×10~4 g·mol~(-1) under the given conditions.~(13)C NMR spectroscopy analysis proves the PE to be linear polyethylene(LPE).
Ansa-Cyclohexyl-bis (4,5,6,7-tertrahydro-l-indenyl) zirconium dichloride (5) was used as catalyst for propylene and ethylene polymerization together with methyl aluminoxane (MAO) as the cocatalyst, Isotactic polypropylene was obtained with the highest activity of 6.37 × 10 ~ 7g PP (molZr) -1 (h -1) .The meso-meso (mmmmm) pentads sequence content of PP was determined by C 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 ° C) is the result of its unique bridged-group structure. Complex 5 / MAO displays also high catalytic activity of 0.46 × 10 ~ 6 to 9.87 × 10 ~ 6g PE (molZr) ~ (-1) h ~ (-1) in the homo-polymerization of ethylene.The visometric molecular weight of PE ranges from 0.97 × 10 ~ 4 to 11.16 × 10 ~ 4 g · mol -1 tions. ~ (13) C NMR spectroscopy analysis proves the PE to be linear polyethylene (LPE).