Polystyrene-block-poly(n-butyl acrylate)-block-polystyrene Triblock Copolymer Thermoplastic Elastomer Synthesized via RAFT Emulsion Polymerization

A series of well-controlled polystyrene-b-poly(n-butyl acrylate)-b-polystyrene triblock copolymers were prepared by emulsion polymerization with a carefully designed amphiphilic macroRAFT (reversible addition−fragmentation chain transfer) agent. The triblock copolymers were produced within four hours and only a few percent of dead chains were estimated. Tensile strength of the materials was a function of composition only and it increased linearly with polystyrene composition up to 50 wt %. The ultimate tensile strength reached 10 MPa with an elongation at break of 500% at the polystyrene composition of 40−50 wt %.