Patent ID: 7919571

Claim:
A polybutadiene characterized in that values of e, f and g derived from the following determinant (I): ( 1.7455 0 - 0.0151 - 0.0454 0.4292 - 0.0129 - 0.007 0 0.3746 ) ⁢ ( log 10 ⁡ ( a / d ) log 10 ⁡ ( a / b ) log 10 ⁡ ( a / c ) ) = ( e f g ) ( I ) (wherein a is a mountain peak value around 1130 cm −1 in a transmittance spectrum through Fourier transform infrared spectroscopy (FT-IR), and b is a valley peak value around 967 cm −1 , and c is a valley peak value around 911 cm −1 , and d is a valley peak value around 736 cm −1 ) satisfy relationships of the following equations (II) and (III): (Calculated value of cis-1,4 bond)= e /( e+f+g )×100≧99 (II) (Calculated value of vinyl bond)= g /( e+f+g )×100≦0 (III), wherein the polybutadiene has a melting point (Tm) of not lower than −5° C.