Behavior of polymeric stars with fullerene core in aqueous solution: structural investigation by neutron and light scattering
Star-shape derivatives of C60 with poly(N-vinylpyrrolidone) chains, grafted to C60, were studied in aqueous solution by small-angle neutron scattering in the range of q=0.04-0.8nm-1 and dynamic light scattering. From SANS data we found the functionality of fullerene center n~4. Really a star's gyration radius ~6nm exceeded the Gaussian molecular size by ~40% and the volume was increased by the factor of 3. Such polymer shells make stars' interaction stronger leading to their association. Dynamic light scattering indicates the formation of extended associates (~1000nm in diameter) involving ~10% of stars.