Abstract
Ethylene/1-hexene was copolymerized by an unbridged zirconocene, (2-PhInd)2ZrCl2/MAO (methyl aluminoxane) at 0°C and 50°C respectively. High copolymerization activity and 1-hexene incorporation were observed at 0°C, with the copolymer formed having random sequence distribution and narrow molecular weight distribution. Ethylene polymerization at 50°C showed high activity, but copolymerization at 50°C showed much lower activity, which decreased sharply with increasing 1-hexene concentration in the monomer feed. Copolymer formed at 50°C showed blocky sequence distribution and broad molecular weight distribution. A mechanism model based on ligand rotation hindered by the propagation chain has been proposed to qualitatively explain the observed phenomena.
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Project (Nos. 29734144 and 20274037) supported by the National Natural Science Foundation of China
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Jian-ding, Y., Zhi-qiang, F. & Wei, W. Strong influences of polymerization temperature on ethylene/1-hexene copolymerization catalyzed by (2-PhInd)2ZrCl2/methyl aluminoxane. J. Zhejiang Univ. Sci. B 6, 1009–1014 (2005). https://doi.org/10.1007/BF02888493
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DOI: https://doi.org/10.1007/BF02888493