| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition having excellent asphalt solubility, or the like, and used for providing asphalt compositions having high softening points, high elongations, or the like, by compounding two kinds of specific block copolymers and specifying bulk density, or the like. SOLUTION: This block copolymer composition for modifying asphalt comprises (A) 98-20 wt.% of a block copolymer comprising two or more of (a) polymer blocks consisting mainly of (i) a monoalkenyl aromatic compound and one or more of (b) polymer blocks consisting mainly of (ii) a dienic compound and (B) 2-80 wt.% of a block copolymer having a mol.wt. of 1/3 to 2/3 based on that of the component A and comprising one or more of the component (a) and one or more of the component (b). The components A and B have each a total component (i) content of 10-50 wt.% and a vinylic bond content of <=70 wt.% in the component (ii), and the block copolymer composition has an MI (G condition) of 0.3-15.0, a bulk density of 0.1-0.7, a particle distribution having a 5 mesh-nonpassing particle content of <=30 wt.% and a 20 mesh-passing particle content of <=30 wt.%, and a total pore volume of 100-2,000 mm<3> /g. |
