DENDRITIC INITIATORS FOR LIVING RADICAL POLYMERIZATIONS - A VERSATILEAPPROACH TO THE SYNTHESIS OF DENDRITIC-LINEAR BLOCK-COPOLYMERS

The first use of polyether dendrons as macromolecular initiators for t he controlled free radical polymerization of vinyl monomers has been d emonstrated. Dendrons containing either a single benzylic TEMPO or hal ide functionality at their focal point have been used for the nitroxid e mediated and atom transfer radical polymerizations, respectively. In both cases, hybrid dendritic-linear block copolymers with well-contro lled molecular weights and low polydispersities can be obtained. The s tructure of the hybrid block copolymers is supported by SEC and spectr al data. All the copolymers exhibit a single Tg, indicating that both blocks are miscible. Hybrid block copolymers difficult or impossible t o prepare by previous techniques have been synthesized to demonstrate the versatility of this approach.