Title: Nonequilibrium design of colloidal interactions

Abstract

Colloidal systems experience interparticle interactions that profoundly impact the physical properties of soft materials, including phase stability, structure formation, and macroscopic transport.  A mechanism to dynamically tune these interactions can provide new avenues for self-assembly and material processing.  While equilibrium colloidal interactions have been well characterized, it has been challenging to develop frameworks for understanding nonequilibrium systems where interactions are dynamically evolving on the order of colloidal timescales.  

In this talk, I will discuss how out-of-equilibrium interactions may be leveraged to precisely control the structure and transport of soft colloidal systems.  Using a field-based theory and Brownian Dynamics simulations, I will first present a proof of concept where surface-mobile polymer coated colloids exhibit interactions that dynamically relax as a function of contact time.  Next, I develop a multiscale framework coupling microscopic interactions to macroscopic dynamics and demonstrate a rich phase space for colloidal self-assembly.  Finally, I consider the implications of nonequilibrium interactions in the rheology of multicomponent suspensions.  This work provides new insight into the dynamics of complex colloidal systems and aids the discovery of ‘smart’ materials whose properties can be controlled through external forcings.