ATRP of Styrene and Methyl Methacrylate with Less Efficient Catalysts and with Alkyl Pseudohalides as Initiators/Chain Transfer Agents

Ligands, such as Me(4)cyclam and anionically charged BPAA, providing low values of k(da) and less efficient for ATRP with alkyl halides, were successfully used for ATRP in the presence of alkyl pseudohalides as initiators/chain transfer agents, resulting in well-controlled PSt and PMMA. Although the catalysts with these ligands provide a poor control for ATRP with alkyl halides as initiators, the pseudohalides such as dithioesters yield well-controlled concurrent ATRP/RAFT. The propagating radicals were generated directly from the CTA in the absence of conventional radical initiators, such as AIBN, that are required for a conventional RAFT polymerization. This system is an example of the synergetic cooperation between ATRP and RAFT polymerization procedures that suppresses new chain generation by direct activation of CTA with a copper complex to supply radicals and utilizes fast chain transfer reactions to provide control of the polymerization.