Synthesis of Polystyrene-block-trans-1,4-polyisoprene-block-polystyrene Triblock Copolymer

Here triblock copolymer synthesis mediated by trans-1,4-polyisoprene is reported for the first time. Carbonyl telechelic trans-1,4-polyisoprene (trans-structure >95%) was synthesized by the epoxidation of trans-1,4-polyisoprene followed by oxidative cleavage. Bromine terminated trans-1,4-polyisoprene was then synthesized by the reduction reaction of carbonyl groups of trans-1,4-polyisoprene to hydroxyl groups followed by end group transformation. Atom transfer radical polymerization of styrene was conducted then using bromine terminated trans-1,4-polyisoprene as macroinitiator. Triblock copolymers were characterized by 1H-NMR, FTIR, GPC, DSC, and XRD.