The present invention provides a rubber composition in which solution viscosity and cold flow are improved. The rubber composition according to the present invention includes 20 to 90 wt% of a polybutadiene (A) produced by a metallocene catalyst, having: a cis-1,4-structure in microstructure being 65 to 95 mol%, a vinyl-1,2-structure in microstructure being 4 to 30 mol%, and a weight average molecular weight (Mw) being 2x105 to 1x106; and includes 10 to 80 wt% of polybutadiene (B) having: a Mooney viscosity (ML1+4, 100°C) being 60 or less, a 5 wt% of styrene solution viscosity (St-cp) being 20 to 110; and St-cp/ML1+4 being 1.0 to 2.5, in which a total of the polybutadiene (A) and the polybutadiene (B) is 60 to 100 wt%.
本发明提供了一种可改善溶液粘度和冷流性的橡胶组合物。根据本发明,橡胶组合物包括 20 至 90 wt%由茂
金属催化剂生产的聚
丁二烯(A),其微观结构中顺式-1,4-结构占 65 至 95 摩尔%,
乙烯基-1,2-结构占 65 至 95 摩尔%:微观结构中顺式-1,4-结构占 65 至 95 摩尔%,微观结构中
乙烯基-1,2-结构占 4 至 30 摩尔%,重量平均分子量 (Mw) 为 2x105 至 1x106;还包括 10 至 80 wt%的聚
丁二烯 (B),其 Mooney 粘度 (ML1+4, 100°C) 为 60 或以下,5 wt%
苯乙烯溶液粘度 (St-cp) 为 20 至 110,St-cp/ML1+4 为 1.0至2.5,其中聚
丁二烯(A)和聚
丁二烯(B)的总重量为60至100 wt%。