In situ 1H- and 27AL-NMR studies on metallocene catalyst systems-Catalysts for olefin polymerization

The process of partial hydrolysis reaction of TMA with water and the interaction of zirconocene dichloride (Cp2ZrCl2) with TMA, MAO, and the in situ partially hydrolyzed products of TMA were studied by in situ 1H‐ and 27Al‐NMR spectroscopy. The 1H‐NMR spectra of MAO samples and the in situ hydrolyzed products of TMA with water under different conditions are different. A new peak at δ = −0.58 ppm in 1H‐NMR spectra is observed, and is supposed to be due to the methyl resonance of MAO with low molecular weight. Alkylation reaction is observed between Cp2ZrCl2 and TMA, MAO, and the in situ hydrolyzed products of TMA, and TMA is supposed to be the actual alkylating agent. 27Al‐NMR studies show that MAO is tetra‐coordinated. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 890–897, 2000