  Colloidal building blocks with re-configurable shapes and dynamic
interactions can exhibit unusual self-assembly behaviors and pathways. In this
work, we consider the phase behavior of colloids coated with surface-mobile
polymer brushes that behave as "dynamic surfactants." Unlike traditional
polymer-grafted colloids, we show that colloids coated with dynamic surfactants
can acquire anisotropic macroscopic assemblies, even for spherical colloids
with isotropic attractive interactions. We use Brownian Dynamics simulations
and dynamic density functional theory (DDFT) to demonstrate that time-dependent
reorganization of the dynamic surfactants leads to phase diagrams with
anisotropic assemblies. We observed that the microscopic polymer distributions
impose unique geometric constraints between colloids that control their packing
into lamellar, string, and vesicle phases. Our work may help discover versatile
building blocks and provide extensive design freedom for assembly out of
thermodynamic equilibrium.
