Catalytic component for the polymerization of olefins obtained by impregnation of a prepolymer with a solution of a catalytic component, and the prepolymer obtained from the catalytic component

Process for the manufacture of a prepolymerized catalytic composition for the polymerization of olefins, comprising:

• a-the manufacture of a prepolymer by prepolymerizing at least one olefin in thepresence of a solid catalyst A, then
• b-the impregnation of the said prepolymer with a solution of a catalyst B, then
• c-the prepolymerization of at least one second olefin in the presence of the impregnated first prepolymer to form the prepolymerized catalytic composition;
• wherein the solid catalyst A contains magnesium, chlorine and titanium atoms, and the prepolymerization in the presence of catalyst A is carried out in the presence of a cocatalyst;
• wherein the catalyst B is selected from compounds of formula MLx in which M represents a transition metal, x represents a number equal to the valency of the transition metal and L represents a ligand coordinated to the transition metal, at least one ligand L being a group with cycloalkadienyl skeleton;
• the catalyst A and the catalyst B containing a transition metal and the catalyst A and the catalyst B being different and not being such that at the same time:
• the catalyst A comprises a group with a cycloalkadienyl skeleton and a compound containing an Al—O bond, and
• the catalyst B comprises two ligands each comprising a cycloalkadienyl skeleton connected to each other by a divalent radical.

Process for the manufacture of a prepolymerized catalytic composition for the polymerization of olefins, comprising:

• a-the manufacture of a first prepolymer by prepolymerizing at least one olefin in the presence of a solid catalyst A, then
• b-the impregnation of the said first prepolymer with a solution of a catalyst B, then
• c-the prepolymerization of at least one second olefin in the presence of the impregnated first prepolymer to form the prepolymenzed catalytic composition;
• wherein the solid catalyst A contains magnesium, chlorine and titanium atoms, and the prepotymerization in the presence of catalyst A is carried out in the presence of a cocatalyst;
• wherein the catalyst B is selected from compounds of formula MLx in which M represents a transition metal, x represents a number equal to the valency of the transition metal and L represents a ligand coordinated to the transition metal, at least one ligand L being a group with cycloalkadienyl skeleton;
• the catalyst A and the catalyst B containing a transition metal and the catalyst A and the catalyst B being different.

A process of preparing a prepolymerized catalytic composition for polymerizing olefins, comprising:

• preparing a first prepolymer by prepolymerizing at least one olefin in the presence of a solid catalyst A and a co-catalyst, wherein the solid catalyst A contains magnesium, chlorine and titanium atoms,
• impregnating the first prepolymer with a solution of a catalyst B, selected from compounds of formula MLx in which M represents a transition metal, x represents a number equal to the valency of the transition metal and L represents a ligand coordinated to the transition metal, at least one ligand L being a group with a modified or unmodified cycloalkadienyl, and
• prepolymerizing at least one second olefin in the presence of the impregnated first prepolymer to form the prepolymerized catalytic composition;
• with the proviso that catalyst A and catalyst B are different and that, if catalyst A comprises a group with a modified or unmodified cycloalkadienyl, then catalyst B does not contain a group with a modified or unmodified cycloalkadienyl;
• and that, if catalyst B comprises a group with a modified or unmodified cycloalkadienyl, then catalyst A does not contain a group with a modified or unmodified cycloalkadienyl.

A process of preparing a prepolymerized catalytic composition for polymerizing olefins, comprising:

• preparing a first prepolymer by prepolymerizing at least one olefin in the presence of a solid catalyst A and a co-catalyst, wherein the solid catalyst A contains magnesium, chlorine and titanium atoms,
• impregnating the first prepolymer with a solution of a catalyst B, selected from compounds having a formula MLx in which M represents a transition metal, x represents a number equal to the valency of the transition metal and L represents a ligand coordinated to the transition metal, at least one ligand L being a group with a modified or unmodified cycloalkadienyl, and
• prepolymerizing at least one second olefin in the presence of the impregnated first prepolymer to form the prepolymerized catalytic composition;
• with the proviso that catalyst A and catalyst B are different and that, if catalyst A comprises a group with a modified or unmodified cycloalkadienyl and a compound containing an Al—O bond, then catalyst B does not comprise two ligands each comprising a modified or unmodified cycloalkadienyl connected to each other by a divalent radical;
• and that, if catalyst B comprises two ligands each comprising a modified or unmodified cycloalkadienyl connected to each other by a divalent radical, then catalyst A does not simultaneously contain a group with a modified or unmodified cycloalkadienyl and a compound containing an Al—O bond.

A process of preparing a prepolymerized catalytic composition for polymerizing olefins, comprising:

• preparing a first prepolymer by prepolymerizing at least one olefin in the presence of a solid catalyst A containing magnesium, chlorine and titanium atoms, and in the presence of a co-catalyst,
• impregnating the first prepolymer with absolution of a catalyst B, selected from compounds having a formula MLx in which M represents a transition metal, x represents a number equal to the valencyof the transition metal, and L represents a ligand coordinated to the transition metal, at least one ligand L being a group with cycloalkadienyl skeleton, and
• prepolymerizing at least one second olefin in the presence of the impregnated first prepolymer to form the prepolymerized catalytic composition;
• wherein catalyst A and catalyst B are different.