| 摘要 |
PURPOSE:To obtain the title compsn. with excellent heat resistance and processability, and with a high balance among softening point, rate of penetration, elongation, cohesive force and grasp of aggregate by compounding each a specified amt. of each specified block copolymer compsn. and straight asphalt. CONSTITUTION:The title compsn. comprises 1-10 pts.wt. block copolymer compsn. consisting of 30-95wt.% (hereinbelow described as %) block copolymer consisting of one or more polymer blocks wherein a vinyl arom. hydrocarbon (e.g. styrene) is a main ingredient and one or more polymer blocks wherein butadiene is a main ingredient and having a content of vinyl arom. hydrocarbon (S) of 10-35wt.% and a content of vinyl bonds in the butadiene parts (V) of 15-55% and satisfying the relation of 35<=S+V<=75 and 5-70% block copolymer constituted of one or more polymer blocks wherein a vinyl arom. hydrocarbon (e.g. styrene) is a main ingredient and one or more polymer blocks wherein isoprene is a main ingredient and having a content of vinyl arom. hydrocarbon of 10-35% and 100 pts.wt. straight asphalt with a rate of penetration of 30-130. |
