| abstract |
A rubber composition and a polybutadiene capable of improving the wear resistance and crack growth resistance of a tire are provided. The following determinant (I): [Wherein, a is a peak peak value near 1130 cm −1 of a transmission spectrum by Fourier transform infrared spectroscopy, b is a valley peak value near 967 cm −1 , and c is near 911 cm −1. The values of e, f, and g derived from [The peak value of d in the vicinity of 736 cm −1 ] are represented by the formula (II): (calculated value of cis-1,4 bond) = The polybutadiene is characterized by satisfying a relationship of e / (e + f + g) × 100 ≧ 99 and formula (III): (calculated value of vinyl bond) = g / (e + f + g) × 100 ≦ 0. [Selection figure] None |