| abstract |
Disclosed are a polybutadiene having a controlled microstructure, a narrow molecular weight distribution, minimal gel content, and a low APHA color, a modified polybutadiene, preparation methods for both, and a rubber-reinforced styrene resin composition using the same. The polybutadiene is characterized in that the ratio (Tcp/ML1+4) of a 5% toluene melting viscosity (Tcp) measured at 25 DEG C and the Mooney viscosity (ML1+4) at 100 DEG C is at least 2.0, the molecular weight distribution (Mw/Mn) is no more than 2.80, the gel content is no more than 0.06 wt%, and the APHA color is no more than 20. |