(54e) A Talk on Bijels, in Honor of John A. Quinn

John A. Quinn was a pioneer who advanced our fundamental understanding of processes that occur at fluid interfaces in the field of chemical engineering with practical implications in separations and reaction processes. John was also an outstanding colleague who formed and nurtured at the University of Pennsylvania our extraordinary department culture of intellectual exchange and interaction. In this talk, I briefly highlight a few examples of his work in the field. Thereafter, I discuss an emerging vehicle for study by chemical engineers in these contexts: Bijel membranes. Bijels, first predicted in simulation (1) and realized by a delicate experimental process, (2) comprise bicontinuous streams of immiscible fluids stabilized by jammed layers of nanoparticles at their interface. We have recently developed a robust and versatile means of fabricating these membranes that exploits a suspension of nanoparticles in a ternary aqueous/oil/co-solvent system. (3) This platform allows a broad range of particles and fluid pairs to be formed into fibers or membranes with tremendous promise in the fields of separations and interphase catalysis. Further, the potential importance of these vehicles in practical application will spur fundamental questions of trapped states and interfacial transport worthy of detailed analysis in the style of Quinn. Finally, this work, performed with colleague Daeyeon Lee at the University of Pennsylvania, embodies Johnâ??s spirit of collaborative endeavor.

(1) Colloidal Jamming at Interfaces: A Route to Fluid-Bicontinuous Gels, K. Stratford et al Science 2005,309, 2198-2201.

 (2) Bijels: a new class of soft materials, Michael E. Cates and Paul S. Clegg Soft Matter, 2008, 4, 2132-2138.

 (3) Continuous Fabrication of Hierarchical and Asymmetric Bijel Microparticles, Fibers, and Membranes by Solvent Transfer-Induced Phase Separation (STRIPS) M.F. Continuous Fabrication of Hierarchical and Asymmetric Bijel Microparticles, Fibers, and Membranes by Solvent Transfer-Induced Phase Separation (STRIPS)Haase, D. Lee, K.J. Stebe, Advanced Materials 2015, 27, 7065-7071.