(142cp) Microscale Transport with Application to Sensing Stability in Non-Aqueous Suspensions

Nichole M. Asermely¹, Shelley L. Anna^1,2 andLynn M. Walker¹

Center for Complex Fluids Engineering

¹Department of Chemical Engineering, ²Department of Mechanical Engineering

Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA

Colloid stability in non-aqueous media is an important aspect of numerous commercial products such as coatings, fuels, and pesticides.  While colloid science in aqueous systems has been intensively studied and well characterized, the interparticle forces which occur in non-aqueous systems and how these connect to macroscopic stability are less understood.  More important is that tools to characterize colloidal interactions and stability in non-aqueous media are not as well developed. Microfluidics offers the capability to rapidly vary experimental parameters, such as solvent quality or stabilizer composition, over a wide range in a single experiment.   The development of microfluidic platforms for high throughput analysis of colloidal stability will require improved understanding of microscale transport in low Reynolds number flow.  We are investigating the microscale transport issues associated with two different approaches to sensing the initial stages of colloidal aggregation for characterization of colloidal stability in non-aqueous systems. The transport and fluid mechanics aspects in characterization of colloidal stability will be presented and analyzed.