| 摘要 |
A hydrogenated block copolymer of no. average mol.wt. 40,000-700,000 is obtd. by hydrogenating a block copolymer (I) or (II) so that at least 80% of the olefinically unsatd. bonds of the block copolymer are hydrogenated. (I) has at least one polymer block A 90 wt.% of which is composed of a vinyl aromatic cpd., at least one polybutadiene block B in which 1,2-vinyl bonds account for 30-70%, and at least one polybutadiene block C in which 1,2-vinyl bonds account for less than 30%, (I) comprising 10-50 wt.% (A), 30-80 wt.% (B) and 5-30 wt.% (C). (II) is one in which the block copolymer (I) is bound to at least one of the polymer block units of A, B and C through a coupling agent residue to extend or branch the polymer chain. |
