| abstract |
(57) [Summary]nA novel solid elastomer block copolymer having excellent oxidative and thermal stability, wherein the end blocks are each a polymer (D polymer) or at least one conjugated diene D, where diene D is a 1,3-conjugated diene structure. Wherein the 2- and 3-carbon atoms are each further bonded to a hydrocarbyl side group (eg 2,3-dimethyl-1,3-butadiene) and the polymerized D units are 1,4 Units are predominant; and at least one internal block is a hydrogenated polymer of at least one conjugated diene I (I polymer), wherein one of the 2- and 3-carbon atoms is further attached to a hydrocarbyl side group. Disclosed are block copolymers as described above, which are attached, the other being further attached to a hydrogen atom (eg isoprene). This block copolymer retains all I polymer units of the precursor block copolymer with sufficient unsaturation so that a sufficient number of D units in the D polymer block will allow vulcanization of the block copolymer upon selective hydrogenation. It can be produced by selective hydrogenation to a state. |