The block copolymers may be prepared by selectively hydrogenating substantially all the I polymer units of a precursor block copolymer with a sufficient number of {HEAD ~ D units} in {TAIL ~ the D polymer blocks} retaining their unsaturation on selective hydrogenation to enable the vulcanization of the block copolymer 
in
The block copolymers may be prepared by selectively hydrogenating substantially all the I polymer units of a precursor block copolymer with a sufficient number of { HEAD ~ D units } in { TAIL ~ the D polymer blocks } retaining their unsaturation on selective hydrogenation to enable the vulcanization of the block copolymer
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH