Preparation and Self-Assembled Toroids of Amphiphilic Polystyrene-C60-Poly(N-isopropylacrylamide) Block Copolymers

An amphiphilic polystyrene-C-60-poly(N-isopropylacrylamide) (PS-C-60-PNIPAAm) block copolymer was successfully prepared through atom transfer radical polymerization, demonstrating the facile approach to obtain two-armed polymer-C-60 nanohybrids, in which the C-60 molecules bond to two different polymeric arms. The chemical structures were characterized with Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The PS-C-60-PNIPAAm block copolymer exhibited self-assembly in chloroform into toroids. The self-assembly of PS-C-60-PNIPAAm, which is usually not observed with diblock copolymers and polymer-C-60 nanohybrids, could be attributed to the selective solubility and the strong interaction between C-60 molecules.