Theoretical and spectroscopic UV study of the EtInd2ZrCl2/MAO, EtInd2ZrCl2/MAO-AlCl3 and EtInd2ZrCl2/MAO-Ethyl benzoate interaction

FERREIRA, MARÍA LUJÁN; BELELLI, PATRICIA GABRIELA; DANIEL EDUARDO, DAMIANI

MACROMOLECULAR CHEMISTRY AND PHYSICS

Wiley

Año: 2001 vol. 202 p. 495 - 511

1022-1352

This work presents a theoretical and experimental study of the active sites formation in the system EtInd2ZrCl2/MAO. Results about the effect of additives as a Lewis acid (AlCl3) or a Lewis base (EB) are also analyzed. The theoretical study takes into account all the known steps in the active site formation: alkylation of zirconocene, formation of a polarized complex metallocene: MAO, formation of a contact ion pair and finally a solvent separated ion pair. Other reactions of the zirconocene with other aluminium alkyls (AlCl3 and AlMe3) are also presented and studied. UV-vis experimental results of the additive effects are reported and explained taking into account the theoretical results. A short review of our results and others is presented to complete and discuss the ideas. The most probable sites are loosened contact ion pairs, not the solvent separated ion pairs.