| 摘要 |
PROBLEM TO BE SOLVED: To obtain an asphalt composition excellent in a high temperature preservation stability and low temperature characteristics, and also excellent in balance of each of the characteristics. SOLUTION: [1] The asphalt composition consists of (1) 0.5-50 pts.wt. block copolymer consisting of a polymer block consisting mainly of at least 2 vinylaromatic hydrocarbons and a copolymer block consisting of at least one isoprene and 1,3-butadiene and/or at least one isoprene, 1,3-butadiene and a vinylaromatic hydrocarbon, in which (a) the content of the vinyl aromatic hydrocarbon in the bock copolymer is <60 wt.%, (b) the content of the total of the isoprene and 1,3-butadiene is >40 wt.% and <=95 wt.%, (c) the weight ratio of the isoprene to 1,3-butadiene is in the range of (90/10)-(15/85), (d) the amount of vinyl bonding is <40 wt.% and (e) the MFR (condition G) is 0.1-100 g/10 min, and (2) 100 pts.wt. asphalt. [2] The bock copolymer is used for the new asphalt. |
