Toward Scalable Nanomanufacturing Using Capillarity

Daeyeon Lee

Department of Chemical and Biomolecular Engineering, University of Pennsylvania

In this talk, I will describe new approaches for scalable manufacturing of nanocomposites with unique structures and properties by exploiting capillary interactions between solid particles and fluids. In the first part of this talk, I will describe our work on generating polymer nanocomposite films (PNCFs) with extremely high loadings of nanoparticles using capillary rise infiltration (CaRI).  Owing to the high loadings of nanoparticles, these PNCFs have extraordinarily high hardness, modulus and scratch resistance. In CaRI, PNCFs are formed by thermally annealing a bilayer of polymer and nanoparticle, which induces imbibition of polymer into the nanoparticle layer. CaRI represents an interesting transport phenomenon in which the size of the fluid molecule (i.e., polymer) is comparable to the pore size in the nanoparticle layer. I will share our current understanding of the transport processes involved in CaRI. By adjusting the amount of polymers undergoing CaRI, we can also generate three-phase nanocomposites, which may have potential applications in the areas of membrane separations and energy storage and conversion. In the second part of this presentation, I will describe our recent efforts in creating bicontinuous interfacially jammed emulsions (BIJELs), which are a new class of soft materials with potential applications in reactive separation, membrane separation and catalysis. We have developed a new method to enable continuous generation of bijel microparticles, fibers and membranes using solvent-transfer-induced phase separation (STRIPS). Transport of molecules with opposite polarity as well as membrane separation of nanoparticles using STRIPS bijels will be demonstrated. Also, a new in situ technique to characterize the mechanical properties of these STRIPS bijel fiber as well as the formation of ultrafiltration membranes using STRIPS will be discussed.