Premium
Kinetic modeling of aggregation and gel formation in quiescent dispersions of polymer colloids
Author(s) -
Lattuada Marco,
Sandkühler Peter,
Wu Hua,
Sefcik Jan,
Morbidelli Massimo
Publication year - 2004
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.200450224
Subject(s) - radius of gyration , colloid , chemical physics , diffusion , aggregate (composite) , hydrodynamic radius , volume fraction , fractal , static light scattering , light scattering , dynamic light scattering , monte carlo method , fractal dimension , radius , gyration , work (physics) , polymer , materials science , statistical physics , scattering , chemistry , thermodynamics , nanotechnology , physics , nanoparticle , optics , mathematics , computer security , mathematical analysis , composite material , geometry , statistics , computer science
In this work, a methodology suitable for the description of aggregation and gel formation processes of polymeric colloidal dispersions in quiescent conditions is presented. The modeling of aggregation is based on the use of populations balance equations to describe the time evolution of the aggregate distribution. Monte‐Carlo simulations are used to generate the structural properties of individual aggregates, which are necessary to compute the average radius of gyration and hydrodynamic radius that are compared to the values measured using light scattering. The agreement between model predictions and measured sizes is good in both diffusion‐limited and reaction‐limited conditions. For the description of progress toward gel formation, the cumulatively occupied volume, a measure of the fraction of space occupied by the clusters, is defined. Due to the fractal nature of clusters, during the aggregation the system can reach a condition of space filling, after which the formation of gel is a result of the interconnection of the clusters. It is found that in diffusion‐limited conditions the interconnection step is much faster than the preceding aggregation, while in reaction‐limited conditions the aggregation and the interconnection are of comparable duration.