Living polymerization of an amphiphilic, helical aramid diblock copolymer

Abstract

We report herein the living polymerization of an amphiphilic, helical aramid diblock copolymer made possible by the utilization of the reagent PHOS3. Two monomers, 2,4-bis((2,5,8,11-tetraoxapentadecan-15-yl)oxy)-5-aminobenzoic acid and 5-amino-2,4-difluorobenzoic acid, were used to build the hydrophilic and hydrophobic blocks, respectively. The diblock copolymer was characterized by NMR and GPC/SEC, and its aggregation behavior was investigated using atomic force microscopy (AFM), (depolarized) dynamic light scattering ((D)DLS), and small-angle X-ray scattering (SAXS). The analysis strongly suggests that the diblock copolymer self-assembles to form elongated, tube-like structures in water.