Jamming in soft materials

Ryan Joseph Larsen

Materials that have both solid and liquid-like properties are important industrially and are ubiquitous in nature. Transitions from liquid-like to solid-like mechanical properties often occur when many solid elements within a material are brought into close contact, or jammed together. This thesis is an exploration of how jamming can cause important changes in material properties. We first show how particle jamming can cause bubbles to become stable to dissolution, a result that has useful implications for industrial applications in areas such as food and cosmetics. The observed stability occurs when particles on the surface of the bubble form a jammed structure that provides mechanical stability and allows the air/liquid interface to assume a shape that is stable to dissolution. A second way to form useful solid-like particle structures is through shear flow. Shear-induced clustering...