Abstract
We studied clustering and gelation in low-volume-fraction () hard-sphere colloids, some with charge, with added non-adsorbing polymers. The rangeof the effective ‘depletion’ attraction induced by the polymers between the particles is of the particles’ diameter. The effects of density mismatch between the particles and thesolvent and unscreened charges on the particles were investigated. The onset of aggregationand gelation in a neutral, density-matched system is discussed in terms of mode-couplingtheory (MCT) and a recent ‘renormalized’ version of MCT respectively. Gravitycauses sedimentation of growing clusters and shifts the gelation boundary. In thecharged and density-matched system, a ‘cluster phase’ in which finite-size aggregates‘coexisted’ with monomers occurred before gelation. Its origins remain unclear.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have