Efficient Processing Pathways to Create High Interface Materials
Whereas physical chemistry and phase separation of the constituents can be used to direct the organization of multiphase materials, processing flows could be an alternative to create intricate multiphase structures. Generating interfaces on the bulk scale through traditional batch- or continuous-mixing processes is, however, energy and material intensive, and offers poor control. Here, we discuss an alternative based on interface creation using laminar flow in specific static mixers that force immiscible streams through splitting and recombination elements, which multiplies the layers per unit volume in a fractal manner and maximizes the area of interfacial contact. These techniques have mainly been used for polymeric systems so far, but the notion of hierarchical and fractal processing can be extended to other classes of soft materials. Increasingly thin multilayered liquid structures are remarkably stable, leading to very small droplets when they finally break up, thus opening a possible route towards energy-efficient emulsification, as will be discussed at the end of this chapter.