MANUFACTURING METHOD FOR MODIFIED CONJUGATED DIENE-BASED POLYMER, MODIFIED CONJUGATED DIENE-BASED POLYMER, AND RUBBER COMPOSITION

PROBLEM TO BE SOLVED: To provide a manufacturing method for a modified conjugated diene-based polymer capable of manufacturing a rubber product excellent in low heat generation property, a low temperature characteristic and wearing-resistance without impairing processability. SOLUTION: The manufacturing method for the modified conjugated diene-based polymer includes a first step of polymerizing a part of a first conjugated diene compound in the presence of a catalyst containing a predetermined component as a main component, a second step of obtaining a first conjugated diene-based polymer having an active terminal end and having a vinyl bond content of less than 10%, a cis-1,4-bond content of 75% or more and a weight average molecular weight (Mw) of 250,000-800,000 and a second conjugated diene-based polymer having an active terminal end and having a weight average molecular weight (Mw) of 10,000-150,000 by further adding a specific component into the reaction system and polymerizing the remaining first conjugated diene compound, and a third step of reacting the active terminal ends of the first and second conjugated diene-based polymers with a modifying agent. COPYRIGHT: (C)2011,JPO&INPIT