Modified conjugated diene-based polymer and method of preparing the same

A modified conjugated diene-based polymer comprising a functional group derived from a modifier represented by Formula 1:

• wherein, in Formula 1,
• R1, R4, and R5 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms,
• R2 is a divalent hydrocarbon group having 1 to 20 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms, and
• R3 is a connecting group represented by Formula 2 or Formula 3,
• wherein, in Formula 2 or Formula 3,
• R6 is a monovalent hydrocarbon group having 1 to 20 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms;
• or a substituent represented by Formula 2-1,
• R7 is a divalent hydrocarbon group having 1 to 20 carbon atoms which unsubstituted or substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms, and
• R8 to R10 are each independently a divalent hydrocarbon group having 1 to 20 carbon atoms which is unsubstituted or substituted with an alkyl group having 1 to 20 carbon atoms,
• wherein, in Formula 2-1,
• R11 is a divalent hydrocarbon group having 1 to 20 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms, and
• R12 and R13 are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms which is unsubstituted or substituted with at least one substituent selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 30 carbon atoms.