| abstract |
An object of the present invention is to provide a polymer composition having properties resembling those of natural rubber, e.g. good durability (fracture resistance, wear resistance, and crack growth resistance), and a method for manufacturing the polymer composition. Specifically, the present invention provides a method for manufacturing a polymer composition including a mixture of polyisoprene and polystyrene/polybutadiene, comprising: polymerizing styrene monomer or butadiene monomer in the presence of a catalyst to synthesize polystyrene or polybutadiene; adding isoprene monomer to the polystyrene or polybutadine thus synthesized, to synthesize polyisoprene and thus generate said mixture, wherein content of the styrene monomer or the butadiene monomer is set to be 10 mol % or less with respect to the total quantity of the styrene monomer/the butadiene monomer and the isoprene monomer. |