title: Stable oxide nanoparticle clusters obtained by complexation.
abstract: We report on the electrostatic complexation between polyelectrolyte-neutral copolymers and oppositely charged 6-nm crystalline nanoparticles. For two different dispersions of oxide nanoparticles, the electrostatic complexation gives rise to the formation of stable nanoparticle clusters in the range 20-100 nm. It is found that inside the clusters, the particles are "pasted" together by the polyelectrolyte blocks adsorbed on their surface. Cryo-transmission electronic microscopy allows visualization of the clusters and determination of the probability distribution functions in size and in aggregation number. The comparison between light scattering and cryo-microscopy results suggests the existence of a polymer brush around the clusters.
authors.affiliation: Matière et Systèmes Complexes, UMR 7057 CNRS Université Denis Diderot Paris-VII, 140 rue de Lourmel, F-75015 Paris, France. jean-francois.berret@paris7.jussieu.fr
authors.forename: J-F
authors.initials: JF
authors.lastname: Berret
authors.forename: A
authors.initials: A
authors.lastname: Sehgal
authors.forename: M
authors.initials: M
authors.lastname: Morvan
authors.forename: O
authors.initials: O
authors.lastname: Sandre
authors.forename: A
authors.initials: A
authors.lastname: Vacher
authors.forename: M
authors.initials: M
authors.lastname: Airiau