Solid-State NMR Investigations of MgCl2 Catalyst Support

MgCl2 is a vital component of Ziegler-Natta catalysts for olefin polymerization. Here we:synthesized anhydrous MgCl2 using different drying protocols and exploited H-1 NMR to quantify the proton content. We report on our study of neat and ball-milled MgCl2 samples by means of Mg-25 and Cl-35 solid-state NMR. DFT calculations of the quadrupole tensor aid in analysis of the spectra. The results show that, due to the morphology of the neat particles, a preferred Orientation is induced which manifests itself in unusual powder line shapes. Ball Milling reduces particle size, which subsequently leads to a small distribution of quadrupole parameters for the bulk. Surface sites, highly relevant for catalysis, are not directly observed, due to their broad lines of low intensity.