Herein we report the facile synthesis of an amphiphilic rod-coil block copolymer obtained by the coupling of an amine-terminated poly(dimethylpropylamine norbornene imide) (PDMAPNI) and a pentafluorophenol ester-terminated poly(dimethoxybenzyl p-aminobenzoate) (PArarn). Postpolymerization amide N-deprotection of the block copolymer yielded a. strongly aggregating water-soluble rod-coil copolymer. Transmission electron microscopy revealed the formation of large ribbonlike aggregates with sizes up to 50 nm in thickness and 300 nm in length.