Precision Synthesis of Hybrid Block Copolymers by Organotellurium‐Mediated Successive Living Radical and Cationic Polymerizations

Living cationic polymerization reactions using organotellurium compounds as initiators are reported. Polymerization of vinyl ethers in the presence of an organotellurium initiator and a Lewis acid, such as In(OTf)(3) and BF(3)·OEt(2), affords well-controlled poly(vinyl ether)s with predetermined molecular weights and narrow molecular-weight distributions. Poly(meth)acrylates possessing organotellurium group at the ω-polymer end, which are prepared using organotellurium-mediated controlled/living radical polymerization (TERP), are used as macroinitiators for living cationic polymerization. The one-pot, two-step reaction of the macroinitiator with vinyl ether under radical and cationic conditions gives well-controlled AB diblock copolymers. ABA triblock copolymers with controlled structures are also synthesized from a bifunctional organotellurium initiator.