BITUMEN MODIFIER AND BITUMEN COMPOSITION

摘要

PURPOSE: To obtain a bitumen modifier which is excellent in solubility in bitumen, softening point, rate of penetration, toughness, and tenacity and gives a bitumen compsn. greatly improved in flow resistance and to obtain a bitumen compsn. contg. the modifier. ;CONSTITUTION: This bitumen modifier is a block copolymer having at least one polymer block mainly comprising vinylarom. hydrocarbon units and at least one polymer block mainly comprising conjugated diene units and has such characteristics that the wt. average mol.wt. is 200,000-1,000,000; that the vinylarom. hydrocarbon content is 5-60wt.%; that at least one polymer block mainly comprising vinylarom. hydrocarbon units is at the molecular end and the amt. of the conjugated diene units has such a tapered distribution that the amt. gradually decreases from the molecular end; and that the block copolymer has a linear structure.;COPYRIGHT: (C)1996,JPO