FIELD: chemistry.
SUBSTANCE: invention relates to a modified conjugated diene-based polymer, a method of its preparation, as well as a rubber composition comprising it. The conjugated diene modified polymer contains a Si atom and a N atom, and the N content of the polymer is 150 ppm or more by weight. The Mooney viscosity change rate (MVR) is 20% or less. A method of producing a modified conjugated diene polymer involves polymerizing a conjugated diene monomer or a conjugated diene monomer and a vinyl aromatic compound monomer in the presence of a polymerization initiator in a carbon solvent to obtain an active first chain; reaction of the active first chain with an alkoxysilane-based modifier to produce a modified active first chain; and reaction of the modified active first chain and a macromonomer containing a repeating unit derived from the N-functional monomer.
EFFECT: resulting polymer has excellent processability and good tensile strength and viscoelastic properties.
17 cl, 3 tbl, 2 ex
