Method for preparing complex styrenic block copolymer and asphalt composition containing it

摘要

Disclosed is a modified asphalt composition obtained by blending asphalt with a complex block copolymer, which is prepared by polymerizing styrene in the presence of an anionic polymerization initiator to prepare a polystyrene solution, adding butadiene to the polystyrene solution, and then further polymerizing styrene, and wherein a triblock copolymer and diblock copolymer are present at a specific proportion. The modified asphalt composition of the present invention exhibits superior ductility at low temperature, while exhibiting comparable or better softening point as compared to conventional compositions, and, thus, is applicable to road paving, waterproof sheets and sealants.