摘要 |
Process for the preparation of crystalline vinylaromatic polymers with a high degree of syndiotaxy which comprises polymerizing vinylaromatic monomers in the presence of a catalytic system essentially consisting of: a) a complex of titanium having the general formula: CpTiX1X2X3 wherein Cp represents a cyclopentadienyl ligand whereas X1, X2, X3, the same or different, are selected from a halogen such as chlorine, or from alkyl groups, alkoxides, carboxylates, di(alkyl)amides; b) a polyalkylaluminoxane wherein the alkyl group contains from 1 to 8 carbon atoms; c) aluminum trifluoride.in |