A neutron spin-echo study of the dynamics of star-shaped polymers (with polystyrene arms grafted to C60) in solutions and in the bulk

Methods of small-angle and inelastic neutron scattering were used to study star-shaped polymers obtained by grafting polystyrene to fullerene C-60 (six arms with an elementary mass M = 5 x 10(3)). The behavior of stars in the solution and bulk was compared with the dynamics of free molecules of polystyrene with a mass equal to the mass of an arm. The slow dynamics of arms in the ranges of times t = 0.01-20 ns, momentum transfers q = 0.2-0.6 nm(-1), and temperatures T = 20-60degreesC does not obey the simple models of Rouse and Zimm. The interaction of the rays with the C-60 fullerene under the conditions of the specific geometry of the macromolecule leads to unusual oscillations of time correlations in the arms of stars. (C) 2002 MAIK "Nauka / Interperiodica".