Catalysts systems for the polymerization and copolymerization of alpha-olefins

A catalyst component for polymerization of alpha-olefins, the catalyst component having a general formula (I)

• wherein:
• M is a transition metal of groups 3-10 of the periodic table of the elements, lanthanide or actinide;
• each X group, equal to or different from each other, is hydrogen, halogen, alkyl, cycloalkyl, aryl, alkenyl, arylalkyl, arylalkenyl or alkylaryl with 1 to 20 carbon atoms, linear or branched, the hydrogens of these groups are optionally substituted by SiR3, GeR3, OR, NR2, OSiR3 groups or any combination thereof wherein R is hydrogen, C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C7-C20 alkenyl, C7-C20 arylalkyl, C7-C20 arylalkenyl or alkylaryl, branched or linear;
• n is a number whose value is:
• 0, 1, 2 or 3, in order to fill remaining free valences of the metal M;
• L is a neutral Lewis base;
• Z is a number whose value is:
• 0, 1, 2 or 3;
• A is a cyclopentadienyl ring of formula C5RI4, wherein each RI group is equal to or different from each other and is hydrogen, C1-C20 alkyl, C3-C20 cycloalkyl, C6-C20 aryl, C7-C20 alkenyl, C7-C20 arylalkyl, C7-C20 arylalkenyl or alkylaryl, branched or linear, the hydrogens of these groups optionally are substituted by SiR3, GeR3, OR, NR2, OSiR3 groups or any combination thereof wherein R is defined in claim 1;
• or RI is SiR3, GeR3, OR, NR2, an OSiR3 group or any combination thereof;
• and wherein two adjacent RI groups optionally unite in order to form a saturated or unsaturated polycyclic cyclopentadienyl ring selected from the group consisting of tetrahydroindenyl and indenyl, optionally substituted with RI groups;
• RII is hydrogen, alkyl, cycloalkyl, aryl, alkenyl, arylalkyl, arylalkenyl or alkylaryl from 1 to 20 carbon atoms, linear or branched, whose hydrogens optionally are substituted by SiR3, GeR3, OR, NR2, OSiR3 groups or any combination thereof wherein R is above defined;
• wherein RII optionally forms a condensed ring through another bond with E;
• E—E is CRIV2—SiRIII2 or SiRIII2—CRIV2;
• each RIII, equal to or different from each other, is hydrogen, alkyl, cycloalkyl, aryl, alkenyl, arylalkyl, arylalkenyl or alkylaryl with 1 to 20 carbon atoms, linear or branched, where hydrogens optionally are substituted by SiR3, GeR3, OR, NR2, OSiR3 groups or any combination thereof wherein R is above defined;
• RIV has the same meaning of RIII or RIV is halogen;
• wherein two groups selected from RIV and RIII and belonging to different E groups optionally form a cyclic structure.