Complex fluid mixtures of surfactants with water and oil self-assemble to form a rich variety of nanostructures that have found important applications in many areas of chemical and materials engineering. Over the past three years, the PI's laboratory has pioneered investigations of a completely new class of anhydrous complex fluids, comprising of surfactant, oil, and sugar that form solid complex glasses. The robust nanostructure of these sugar-based complex glasses, and the ease with which they can be dissolved afterwards in water, make them eminently useful as templates for the preparation of rod-like, sheet-like, and bicontinuous nanomaterials with wide ranging practical applications. The thermodynamically driven spontaneous mixing of hydrophobic compounds in complex glasses also opens new avenues for direct encapsulation of oils and preservation of pharmaceuticals and proteins. Results from the proposed work to understand glass formation in sugar-based complex glasses will establish the foundation for a broader career-defining research program in glass formation from non-aqueous complex fluids including for example, molten salts and low melting point metal alloys that combine magnetic, electronic, and catalytic properties with the rich nanostructures of complex fluids.
New science and exciting applications await discovery at the intersection of glasses with complex fluids. This CAREER proposal seeks support that will catalyze efforts towards establishing the fundamental principles underlying glass formation in complex fluids. An array of preliminary results demonstrates glass formation in complex fluids and the feasibility of the proposed studies. These include: (1) phase behavior characterization; (2) modulated differential scanning calorimetry measurements of the glass transition; (3) electron microscopy; (4) small angle scattering measurements of microstructural length scales; (5) magnetic resonance imaging and self-diffusion measurements of microstructural topology/connectivity; and (6) rheological characterization of the complex glasses in their molten state. To demonstrate the practical utility of these complex glasses, the PI presents preliminary results for two specific applications: (1) environmentally friendly, solvent-free preparation of polydivinylbenzene membranes, and (2) high-efficiency, spontaneous encapsulation of >50 vol% limonene, the principal component of orange oil, in an edible solid microemulsion glass.
Broader Impact: The educational objective proposed here further integrates the PI's research expertise to lead a curriculum reform effort that elevates product design, rooted at the molecular-level, to the same level as the archetypal Chemical Engineering capstone course in plant design. To bring together concepts taught in a sequence of new pilot courses, the PI will develop a common case study on laundry detergents, which ties together knowledge of colloids and interfacial phenomena, polymers, inorganic chemistry, enzyme catalysis, encapsulation, powder processing, and broader ecological and intellectual property considerations. Other academic institutions will access lecture and laboratory modules through the WWW and the PI will make a technically simplified available to K12 students and teachers. The PI will assess the effectiveness of this curriculum reform effort, which will be implemented in stages on two parallel undergraduate sections, through a mandatory annual cooperative education cycle. Student, faculty, and industrial evaluations will be used to fine-tune the course content and test the commonly held belief that innovative product design has become a necessary skill for domestic chemical engineers as traditional engineering functions and production are transferred overseas.
