A bis-imine pyridine complex of lanthanides having general formula (I): ##STR00001## Said bis-imine pyridine complex of lanthanides having general formula (I) can be advantageously used in a catalytic system for the (co)polymerization of conjugated dienes.

A bis-imine pyridine complex of lanthanides having general formula (I): ##STR00001## Said bis-imine pyridine complex of lanthanides having general formula (I) can be advantageously used in a catalytic system for the (co)polymerization of conjugated dienes.

A bis-imine pyridine complex of lanthanides having general formula (I): ##STR00001## Said bis-imine pyridine complex of lanthanides having general formula (I) can be advantageously used in a catalytic system for the (co)polymerization of conjugated dienes.

A polymer blend consisting of (a) 60-96 percent by weight of a high molecular weight elastomeric polymer, (b) 4-35 percent by weight of a low molecular weight aromatic hydrocarbon polymer, and optionally (c) 0-13 percent by weight of an extender oil, wherein the amounts of the components (a), (b) and (c) are based on the total weight of the polymer blend.

A polymer blend consisting of (a) 60-96 percent by weight of a high molecular weight elastomeric polymer, (b) 4-35 percent by weight of a low molecular weight aromatic hydrocarbon polymer, and optionally (c) 0-13 percent by weight of an extender oil, wherein the amounts of the components (a), (b) and (c) are based on the total weight of the polymer blend.

A polymer blend consisting of (a) 60-96 percent by weight of a high molecular weight elastomeric polymer, (b) 4-35 percent by weight of a low molecular weight aromatic hydrocarbon polymer, and optionally (c) 0-13 percent by weight of an extender oil, wherein the amounts of the components (a), (b) and (c) are based on the total weight of the polymer blend.

A method of production of modified conjugated diene rubber includes causing an aromatic compound having three or more carbon atoms directly bonded to an aromatic ring in one molecule to react with an alkali metal atom so as to obtain an alkali metal-reacted aromatic compound; polymerizing a monomer at least containing a conjugated diene compound by using the alkali metal-reacted aromatic compound so as to obtain a conjugated diene rubber having an active end; causing the active end of the conjugated diene rubber having an active end to react with an activity control agent so as to obtain a conjugated diene rubber reacted with an activity control agent; and causing the active end of the conjugated diene rubber reacted with an activity control agent to react with a modifier having an alkoxy group and a halogen atom-containing group so as to obtain a modified conjugated diene rubber.

A method of production of modified conjugated diene rubber includes causing an aromatic compound having three or more carbon atoms directly bonded to an aromatic ring in one molecule to react with an alkali metal atom so as to obtain an alkali metal-reacted aromatic compound; polymerizing a monomer at least containing a conjugated diene compound by using the alkali metal-reacted aromatic compound so as to obtain a conjugated diene rubber having an active end; causing the active end of the conjugated diene rubber having an active end to react with an activity control agent so as to obtain a conjugated diene rubber reacted with an activity control agent; and causing the active end of the conjugated diene rubber reacted with an activity control agent to react with a modifier having an alkoxy group and a halogen atom-containing group so as to obtain a modified conjugated diene rubber.

The present invention relates to a polymerization initiator represented by Formula 1, a modified conjugated diene-based polymer, methods for preparing them, a rubber composition comprising the modified conjugated diene-based polymer, and a tire prepared from the rubber composition. ##STR00001## (In Formula 1, the definition of each substituent is the same as defined in the description.)

The present invention relates to a polymerization initiator represented by Formula 1, a modified conjugated diene-based polymer, methods for preparing them, a rubber composition comprising the modified conjugated diene-based polymer, and a tire prepared from the rubber composition. ##STR00001## (In Formula 1, the definition of each substituent is the same as defined in the description.)