The present invention provides a modified butadiene-based polymer capable of enhancing dispersability of an inorganic filler when used in a rubber composition, and enhancing viscoelasticity, a tensile property and processibility of the rubber composition in a balanced way from an interaction with the inorganic filler, and a modifier useful for preparing the same.

The present invention relates to a modified styrene-butadiene copolymer with a high modification ratio, including a functional group derived from a modifier represented by Formula 1, a preparation method thereof, a rubber composition including the same, and a tire manufactured from the rubber composition.

The present invention relates to a modified styrene-butadiene copolymer with a high modification ratio, including a functional group derived from a modifier represented by Formula 1, a preparation method thereof, a rubber composition including the same, and a tire manufactured from the rubber composition.

According to an embodiment of the present invention, there is provided a method of preparing a rubber composition, which includes (a) synthesizing a living polymer by solution polymerization of a monomer mixture including a conjugated diene-based monomer in the presence of a first catalyst; (b) reacting some ends of the living polymer with a coupling agent; (c) reacting the remaining ends of the living polymer with an organotin halide compound to prepare an end-modified conjugated diene-based polymer solution; and (d) adding a second catalyst and a conjugated diene-based monomer to the end-modified conjugated diene-based polymer solution to induce solution polymerization.

Disclosed are a modified conjugated diene-based polymer represented by a specific Chemical Formula and a method of preparing the same.

Disclosed are a modified conjugated diene-based polymer represented by a specific Chemical Formula and a method of preparing the same.

A modified conjugated diene polymer obtained by modifying a conjugated diene polymer that is obtained by polymerizing a conjugated diene compound or polymerizing a conjugated diene compound and an aromatic vinyl compound is produced by a production method comprising a first modification step wherein an unsaturated binding site at least either in the skeleton or at the side chain of the conjugated diene polymer is reacted with a first compound having a group 4 or 13 element of the periodic table.

A modified conjugated diene polymer obtained by modifying a conjugated diene polymer that is obtained by polymerizing a conjugated diene compound or polymerizing a conjugated diene compound and an aromatic vinyl compound is produced by a production method comprising a first modification step wherein an unsaturated binding site at least either in the skeleton or at the side chain of the conjugated diene polymer is reacted with a first compound having a group 4 or 13 element of the periodic table.

Disclosed are an end-functionalized conjugated diene-based polymer represented by Chemical Formula 1 and a method of preparing the same.

Disclosed are an end-functionalized conjugated diene-based polymer represented by Chemical Formula 1 and a method of preparing the same.