The aggregation behavior of colloidal particles in liquid crystal can lead to the formation of new aggregate morphologies and fractal structures. Here we report the one pot synthesis of colloidal aggregates in nematic liquid crystal brought about by the isotropic to nematic phase transition. These aggregates are highly anisotropic on short length scales, with web-like morphologies composed of hollow capsules organized into chains. After performing a temperature quench, the capsules are formed within one second. Shortly after formation, the capsules spontaneously assemble into chains, which subsequently organize into clusters. As the number density of capsules increases with quench depth, these clusters form a gel-like morphology consisting of densely packed chains of capsules. We use confocal fluorescence microscopy over a wide range of length scales to measure aggregate structure as a function of quench depth. Over time, these aggregates undergo aging and become more compact, which we quantify using a pair correlation function, g(r). Velocity analysis reveals that ageing effects are combination of Frank elasticity relaxation, and defect line breakage/shrinkage.

Frank elasticity driven gelation and aging of self-assembled hollow colloids

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.