Activation and Deactivation of the Polymerization of Ethylene over rac-EtInd(2)ZrCl(2) and (nBuCp)(2)ZrCl2 on an Activating Silica Support

作者：Tisse Virginie F; Boisson Christophe; McKenna Timothy F L^*

来源：Macromolecular Chemistry and Physics, 2014, 215(14): 1358-1369.

DOI：10.1002/macp.201400023

• activating supports
• deactivation
• metallocene
• molecular-weight distribution
• polyethylene

A study is carried out in order to better understand the kinetic behavior of two different metallocene precursors supported on an activating silica support, and, in particular, to attempt to reduce the significance of catalyst deactivation through the use of different alkylating agents. It is observed that it is difficult to prevent the deactivation of the rac-EtInd(2)ZrCl(2) sites on the activating support, and, furthermore, the deactivation is accompanied by the disappearance of sites producing the highest-molecular-weight polymer. On the contrary, with the (nBuCp)(2)ZrCl2 precursor, it is possible to manipulate the addition of either tri-isobutylaluminum (TIBA) or triethylaluminum (TEA) to significantly reduce the deactivation of the catalyst on the activating supports. Finally, the molecular-weight distribution seems to depend much more on the intrinsic properties of the active sites than on how the active sites are treated.

• 出版日期2014-7