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Title: Role of interaction range on the microstructure and dynamics of attractive colloidal systems
Colloidal gelation phase diagram has been traditionally characterized using three key factors: particle volume fraction, strength of attraction, and range of attraction. While there's a rich body of literature on the role of attraction strength and particle volume fraction, majority of studies have been limited to short range interactions. Using Brownian dynamics simulations, we explored the effect that the range of attractions has on the microstructure and dynamics of both weakly and strongly attractive colloidal systems. Although gelation occurs significantly faster at high attraction strength, by an order of magnitude compared to low strength, we did not observe any clear trend in gelation-rate with respect to a change in the range of interaction. However, as the attraction range increases in both systems, the final structure undergoes a transition from a single connected network to a fluid of dense clusters. This results in a new gelation phase boundary for long range attractive colloids.  more » « less
Award ID(s):
2118962
PAR ID:
10546780
Author(s) / Creator(s):
;
Publisher / Repository:
Royal Society Chemistry
Date Published:
Journal Name:
Soft Matter
Volume:
20
Issue:
22
ISSN:
1744-683X
Page Range / eLocation ID:
4466 to 4473
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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