Polymer, Vol.43, No.9, 2769-2775, 2002
Static and dynamic light scattering study of strong intermolecular interactions in aqueous solutions of PVP/C-60 complexes
The investigations of the dilute aqueous solutions of polyvinylpyrrolidone/fullerene (PVP/C-60) complexes by static (SLS) and dynamic (DLS) light scattering showed that strong intermolecular interactions, effective on the distances of about 45-50 nm, take place in the solutions. Two concentration ranges are well distinguished in these solutions. Above a critical concentration (c(cr)) the fluctuations in the solutions are hindered and only one, diffusive, mode is observed in DLS experiments. Upon dilution (c < c(cr)) this unified structure divides into large fragments (domains) and the slow mode attributed to long-range concentration fluctuations, gradually appears. The angular and concentration dependencies of the diffusion coefficient of the slow mode indicate the existence of strong intermolecular interactions.