Core-Functionalized Star Polymers by Transition Metal-Catalyzed Living Radical Polymerization. 1. Synthesis and Characterization of Star Polymers with PMMA Arms and Amide Cores

Abstract

A series of microgel core-functionalized star-shaped polymers were synthesized by the polymer linking reaction method in RuCl2(PPh3)3-catalyzed living radical polymerization. The synthesis was achieved by the polymer linking reaction method; i.e., functionalized divinyl compounds were added in situ to the solution of linear living poly(MMA)s prepared with the Ru(II)-catalyzed living radical polymerization. The functionalized microgel cores thus obtained contained acrylamide and methacrylamide. Also, star polymers with varying densities of the microgel cores were prepared from diacrylamides with various lengths and structures of the spacer, and by changing the relative amounts of MMA (arm length) and divinyl compound (core size) to initiator, a variety of core-functionalized star polymers could be obtained in high yield, These core-functionalized star-shaped polymers have f of 20−640, Mw of 3.3 × 105−1.3 × 107, and Rz of 5−42 nm. These results indicated that the cores carry as many as 440−51 000 amide grou...