The role of quench rate in colloidal gels

Abstract

Interactions between colloidal particles have hitherto usually been fixed by the suspension composition. Recent experimental developments now enable the control of interactions \emph{in-situ}. Here we use Brownian dynamics simulations to investigate the effect of controlling interactions on gelation, by "quenching" the system from an equilibrium fluid to a gel. We find that, contrary to the normal case of an instantaneous quench, where the local structure of the gel is highly disordered, controlled quenching results in a gel with a higher degree of local order. Under sufficiently slow quenching, local crystallisation is found, which is strongly enhanced when a monodisperse system is used. The higher the degree of local order, the smaller the mean squared displacement, indicating an enhancement of gel stability.

References in corpus (8)

• Colloidal Gels: Equilibrium and Non-Equilibrium Routes
• Phase behavior of a fluid with competing attractive and repulsive interactions
• Arrested phase separation in a short-ranged attractive colloidal system: A numerical study
• Crystallization and gelation in colloidal systems with short-ranged attractive interactions
• Simple models for two-dimensional tunable colloidal crystals in rotating ac electric fields
• Lamellar order, microphase structures and glassy phase in a field theoretic model for charged colloids
• The effect of attractions on the local structure of liquids and colloidal fluids
• C60: the first one-component gel?

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