Synthesis of the four‐arm star‐block copolymer [PVC‐b‐PBA‐CH(CH3)COOCH2]4C by SET‐DTLRP initiated from a tetrafunctional initiator

Pentaerythritol tetrakis(2‐iodopropionate) was used as a tetrafunctional initiator for the Na2S2O4 catalyzed SET‐DTLRP of n‐butyl acrylate in water at room temperature. The resulting tetrafunctional poly(n‐butyl acrylate) macroinitiator with Mn = 14,864 or Mn = 3627 per arm was used to initiate the SET‐DTLRP of vinyl chloride and provide the first examples of four‐arm star‐block copolymers [PVC‐b‐PBA‐CH(CH3)COOCH2]4C. The Mn of the PVC segment from each arm of the four‐arm star‐block copolymer varied between 353 and 33,622.