title: Destabilization of polystyrene latex particles induced by adsorption of polyvinylamine: mass, size and structure characteristics of the growing aggregates.
abstract: The obviously visible aggregation of suspended colloidal particles resulting from the addition of polyvinylamine to the aqueous dispersion of polystyrene latex particles bearing surface sulfate groups set in with a delay of 24 h. The aggregation mechanisms and the fractal dimension of the aggregates were derived from the variations with time of the weight and number averaged masses of the aggregates as well as of the weight averaged harmonic mean diameter of the size distribution. Since the establishment of starved layers was determined to be relatively fast and to leave the liquid phase free of polymer, the delay for the obvious destabilization was attributed to the reconformation of adsorbed macromolecules that was expected to be extremely slow. This reconformation promoted the emergence of the diffusion-limited aggregation process that accompanies the permanent reaction-limited aggregation process. The fractal dimension of the latex particles/polyvinylamine aggregates was determined to be 2.12.
authors.affiliation: Institut Charles Sadron, 6 rue Boussingault, 67083 Strasbourg Cedex, France.
authors.forename: Otman
authors.initials: O
authors.lastname: Oulanti
authors.forename: Josiane
authors.initials: J
authors.lastname: Widmaier
authors.forename: Emile
authors.initials: E
authors.lastname: Pefferkorn
authors.forename: Simon
authors.initials: S
authors.lastname: Champ
authors.forename: Helmut
authors.initials: H
authors.lastname: Auweter