Patent ID: 7851537
Filing Date: 2010-12-14
Classification: B60C,C08K,C08L

Abstract:
1. A rubber composition for tire, comprising: (a) 5-90 weight parts of a high cis polybutadiene having a cis structure in a proportion of 95 wt % or higher in a microstructure analysis; (b) 90-5 weight parts of a diene-based rubber other than (a); and (c) 1-100 weight parts of a reinforcing agent blended in 100 weight parts of a rubber component including (a)+(b), wherein the high cis polybutadiene is synthesized using a cobalt-based catalyst and satisfies the requirements of: (i) a Mooney viscosity (ML) of 40-49; (ii) a molecular weight distribution [Weight average molecular weight (Mw)/Number average molecular weight (Mn)] of 3.0-3.9; and (iii) a velocity dependence index (n-value) of the Mooney viscosity of 2.3-3.0 (the n-value is represented by Expression 1): (Expression 1) (where RS indicates revolutions per minute of a rotor; and K an arbitrary number).