abstract |
bimodal ndbr. the present invention relates to polybutadiene catalyzed by high molecular weight bimodal neodymium which has a high proportion,> 95%, of cis-1,4 units and a low proportion, <1%, of 1,2-vinyl content, in that polybutadiene has a main linear polymeric fraction and a long-chain polymeric fraction, where the slope in the rgm ratio is> 0.5 for the long-chain polymeric fraction. |