the helgeson lab:

   soft matter design and processing

Nanoemulsion design and assembly


Droplets exhibit unique behavior when driven to the nanoscale, i.e., when the range of colloidal interactions between droplets approaches their size. We have designed novel nanoemulsions to better understand this emergent behavior, and to harness it for the engineering of new materials with novel properties. Ongoing projects in this area include:





Particulates and gels for nanobiotechnology


Nanotechnology has opened up entirely new avenues for interfacing materials with biological systems. Significant advances in this area have been made by focusing on how material chemistry controls function and interactions. By contrast, our approach is to understand how mesoscale structure and properties can be used to impart new or enhanced functionality. Examples include:





Flow-induced structuring of colloidal fluids


Since structuring of colloids relies on relatively weak forces, imparting flow can be both boon and bane: it can be used to sculpt a fluid's microstructure, but this flow-induced structure can cause flow instabilities that complicate processing. We use unique methods that elucidate the complex coupling of microstructure and flow in colloidal systems. We focus particularly on complex flows, i.e., mixtures of shearing and elongation, to simulate the deformations enountered in realistic processing flows. Examples include:





New tools for probing multi-scale fluid structure and dynamics


Inherent to the study of complex fluids is the need to characterize their structure and dynamics at a spectrum of length scales ranging from nanometers to several microns. To facilitate our research, as well as to serve the broader soft matter community, we continually develop and refine methods that give rich, multi-scale information about complex fluids. Click each link to learn more: