Synthesis of AB2 3- and AB4 5-Miktoarm Star Copolymers Initiated from Dendritic Tri- and Penta-Functional Initiators by Combination of Ring-Opening Polymerization of ε-Caprolactone and Nitroxide-Mediated Radical Polymerization of Styrene

✍ Scribed by Yozo Miura; Yumi Sakai; Keisuke Yamaoka

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 186 KB
• Volume: 206
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200400353

✦ Synopsis

Abstract

Summary: Well‐defined AB~2~ 3‐ and AB~4~ 5‐miktoarm star copolymers were prepared by combination of ring‐opening polymerization (ROP) and nitroxide‐mediated radical polymerization (NMRP) using dendritic tri‐ and penta‐functional initiators. Initially, two kinds of dendritic initiators having one benzylic OH and two or four TEMPO‐based alkoxyamine moieties were prepared. Using them, ROP of ε‐caprolactone was carried out at room temperature to give poly(ε‐caprolactone)s carrying two or four alkoxyamine moieties. NMRP of styrene from the poly(ε‐caprolactone)s was carried out at 120 °C to give AB~2~ 3‐ and AB~4~ 5‐miktoarm star copolymers, which were analyzed by ^1^H NMR and SEC. The $\overline M _{\rm n} {\rm s}$ increased linearly with conversion and the $\overline M _{\rm w} /\overline M _{\rm n} {\rm s}$ were in the range 1.10–1.37, showing that well‐defined AB~2~ 3‐ and AB~4~ 5‐miktoarm star copolymers were formed.

Well‐defined AB~2~ 3‐ and AB~4~ 5‐miktoarm star copolymers were prepared by combination of ring‐opening polymerization (ROP) and nitroxide‐mediated radical polymerization (NMRP) using dendritic tri‐ and penta‐functional initiators.

magnified imageWell‐defined AB~2~ 3‐ and AB~4~ 5‐miktoarm star copolymers were prepared by combination of ring‐opening polymerization (ROP) and nitroxide‐mediated radical polymerization (NMRP) using dendritic tri‐ and penta‐functional initiators.