MgCl₂‐supported Ziegler‐Natta catalysts: A structural investigation by X‐ray diffraction and Fourier‐transform IR spectroscopy on the chemical activation process through MgCl₂‐ethanol adducts

Abstract

Abstract By X‐ray diffraction on polycrystalline powders and Fourier‐transform IR spectroscopy, some adducts MgCl 2 (C 2 H 5 OH) x were studied, having different composition in the range from x = 0 (α‐MgCl 2 ) to x = 6. For 2 < x ≤ 6, the structure of such adducts shows prevalently ionic MgCl bonds. For x ≤ 2, covalent bonds are observed among chlorine and magnesium atoms, which give rise to chain compounds through chlorine bridges among the Mg‐atoms. The obtained structural data are also discussed in terms of the synthesis of some MgCl 2 ‐based supports which are very active in the Ziegler‐Natta process of olefin polymerization, after a treatment with titanium halides and a successive addition of a cocatalyst and of other suitable donors.