| 摘要 |
A bituminous composition which comprises a bituminous component and a block copolymer which comprises at least two blocks of a conjugated diene and at least two blocks of a monovinylaromatic hydrocarbon, being of the general formula: S1--B1--S2--B2 wherein B1 is a block of polymerized conjugated diene comprising at least 50 mole% isoprene having an apparent molecular weight of from 180,000 to 400,000, S1 and S2 are blocks of polymerized monovinylaromatic hydrocarbon having a weight average molecular weight of 12,000 to 40,000, and B2 is a block of polymerized conjugated diene comprising at least 50 mole% isoprene having an apparent molecular weight of from 15,000 to 60,000; wherein the weight ratio W of B1 over B2 is in the range of 3.0 to 12.0; and wherein the content of polymerized monovinylaromatic hydrocarbon is in the range from 10 to 35 %wt. |
