Synthesis of star polymers based on xanthate-mediated controlled radical polymerization of N-vinylcarbazole

Poly(N-vinylcarbazole) [poly(NVC)] stars were synthesized by macromolecular design via interchange of xanthate (MADIX)/reversible addition-fragmentation chain transfer (RAFT) polymerization. Four-armed poly(NVC) stars with controlled molecular weights and low polydispersities were obtained using a tetrafunctional xanthate, in which the stabilizing groups are linked to the core. The controlled character of the polymerization was also confirmed by the linear increase in the molecular weight with the conversion. The comparison of the polymerization behaviors using the tetrafunctional xanthate and a monofunctional one suggested that the multifunctional core has a clear effect on the polymerization kinetics, but has no significant influence on the controlled character of the polymerization.