| 摘要 |
There is disclosed a linear block copolymer comprising at least one triblock I-B-I, wherein I is a block of at least one polymerized conjugated diene of at least five (5) carbon atoms, such as isoprene, and B is a block of a polymer of at least one conjugated diene, different from that used to polymerize the block I, of at least four (4) carbon atoms, such as butadiene. The B block is selectively hydrogenated, while each of the I blocks is unhydrogenated and therefore retains a sufficient amount of its original unsaturation to vulcanize the copolymer. There is also disclosed an alternative linear block copolymer containing at least one triblock of the first polymer block made from a minor proportion of at least one aryl-substituted olefin, such as styrene, and a major proportion of at least one conjugated diene used to polymerize the block I, the second middle polymer block of at least one diene used to polymerize the block B, and the third polymer block which is the same as the first polymer block. In this alternative copolymer, the middle block is also selectively hydrogenated, thereby leaving the terminal polymer blocks with a sufficient amount of their original unsaturation to vulcanize the copolymer. The polymers can be crosslinked or functionalized through the terminal blocks containing the vinyl unsaturation. There are also disclosed random linear and star-branched block and random copolymers made from the same monomers as the linear block copolymers. Also disclosed are methods of producing the polymers and selectively hydrogenating the aforementioned polymerized dienes.
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