| abstract |
ABSTRACT OF DISCLOSURE Disclosed are catalysts for the polymerization of alpha-olefins which comprise the reaction product of: (a) an Al-alkyl compound; (b) a silicon compound containing at least one Si-OR or Si-OCOR or Si-NR2 bond, R being a hydrocarbyl radical; (c) a solid comprising, as essential support, a Mg dihalide in active form and, supported thereon, a Ti halide or a halo-Ti-alcoholate and a particular type of electron donor compound. The present invention refers to new supported com-ponents of catalysts for the polymerization of CH2=CHR olefins wherein R is an alkyl radical with 1 to 4 carbon atoms, or an aryl radical, and mixtures of said olefins with ethylene and the catalysts obtained from said components. |