Abstract: Catalyst component for the polymerization of alpha-olefins in solution, in suspension, in gas phase at low and high pressure and temperature or in mass at high pressures and high or low temperatures, characterized in that is defined by general formulas I or II wherein: R, equal to or different from each other, is hydrogen or a radical which contains from 1 to 20 carbon atoms; this group optionally contains heteroatoms of groups 14 to 16 of the periodic table of the elements and boron; at least one group R contains a group OSiR?3, Q is selected from a group comprising: boron or an element from groups 14 or 16 of the periodic table; m value can change from 1 to 4 and it preferably is 1 or 2; L, equal to or different from each other, is a cyclic organic group united to M through a ? bond, or it is an atom from groups 15 or 16 of the periodic table; L1 and L2, equal to or different from each other, have the same meaning of L; M is a metal from groups 3, 4, 10 of the periodic table, lanthanide or actinide.

Abstract: Heterogeneous catalytic compositions obtained by reacting a porous inorganic support with an alumoxane and subsequently supporting at least one metallocene compound thereon. A process for polymerization of ?-olefins in a slurry or in a gas phase, the process catalyzed by such heterogeneous catalytic compositions.

Abstract: Catalyst component for the polymerization of alpha-olefins of general formula (I) wherein: M is a transition metal of groups 3, 4-10 of the periodic table of the elements, Each X group can be equal or different and it is hydride, halogen, alkyl, cycloalkyl, aryl, alkenyl, arylalkyl, arylalkenyl or alkylaryl with 1 to 20 carbon atoms, linear or branched. L is a neutral Lewis base A is a ring with delocalized &pgr; electrons, that directly coordinates to the transition metal M. Each E group can be equal to or different from each other and it is BRIII, CRIV2, SiRIII2, GeRIII2; at least one E is SiRIII2. RII is hydrogen, alkyl, cycloalkyl, aryl, alkenyl, arylalkyl, arylalkenyl or alkylaryl from 1 to 20 carbon atoms, linear or branched, whose hydrogens can be substituted by SiR3, GeR3, OR, NR2, OSiR3 or any combination of thereof. It can moreover form a condensed ring through another bond with E.

Abstract: Catalyst component for the polymerization of alpha-olefins in solution, in suspension, in gas phase at low and high pressure and temperature or in mass at high pressures and high or low temperatures, characterised in that is defined by general formulas I or II 1

Abstract: The invention relates to heterogeneous catalytic systems obtainable by reacting a porous inorganic support with an alumoxane and subsequently supporting at least one metallocene compound thereon, characterized in that the metallocene compound is defined by the following general formulas: 1

Abstract: Catalyst component for the polymerization of alpha-olefins of general formula (I) ##STR1## wherein: M is a transition metal of groups 3, 4-10, lanthanide or actinide of the periodic table of the elements; A is a ring with delocalized .pi. electrons, L is a neutral Lewis base; m is an integer whose value can be: 0 or 1; E is selected from the group comprising: BR.sup.II, CR.sup.II.sub.2, SiR.sup.II.sub.2, GeR.sup.II.sub.2 ; Hal is selected from the group comprising iodine, bromine or chlorine; R.sup.III has the same meaning of R.sup.II ; Si is a silicon atom; D is selected from the group comprising: O, S, NR.sup.IV, PR.sup.IV, OR.sup.IV, SR.sup.IV, NR.sup.IV.sub.2, PR.sup.IV.sub.2 ; each X group equal to or different from each other is selected from the group comprising hydrogen, halide, alkyl, cycloalkyl, aryl, alkenyl, arylallyl, arylalkenyl or alkylaryl with 1 to 20 carbon atoms, n is a number whose value can be: 0, 1, 2 or 3, in order to full the remaining valences of metal M.