(430e) Soft Polymer Composites for Improved Quality of Life

Human facing technologies are constantly in need of innovation with respect to the interaction between the body and the device. This may be due to the need for increased sensitivity, for diagnostics, health monitoring, or actuation. Better interaction may be due to a need for improved comfort or safety, which are critical to the actual utilization of any new device. Improved human-machine interfaces also drive the need for lighter weight devices with lower power needs. Achieving all of these goals simultaneously, while maintaining the electrical and mechanical properties of the device and device materials is an enormous challenge; a challenge that is uniquely suited to polymer composites. Polymers are frequently used in applications that require lightweight materials with controlled thermal properties and a high degree of toughness and durability. Most polymers, however, lack useful electromagnetic properties, which makes the realization of fully polymeric devices for human-facing or biomedical applications a challenge. Polymer composites, a generic term for the addition of fillers or non-polymer inclusions into a polymer matrix, however, enable the combination of the positive aspects of polymers with new materials that have needed electromagnetic behavior. This talk will focus on polymer composites of soft materials, primarily elastomers or controlled polymeric liquids, blended with magnetic or conductive particles. Magnetic composites, specifically magnetorheological fluids, are excellent actuators that take advantage of particle alignment when magnetized. This talk will demonstrate our work understanding the fundamentals of magnetorheological flow in addition to the impacts of non-magnetic additives to properties such as yield stress and viscosity. Similarly, this work will discuss the fluid mechanics associated with the creation and utilization of elastomer composites of room temperature liquid metals, a filler that imparts high dielectric permittivity to the host matrix while minimizing dielectric loss. The composite is created through the rupture of bulk liquid metal and the creation of new interfaces, so it is critical to understand the relationships between interfacial energy and resulting viscosity and modulus. With the understanding of the relationship between fluid mechanics, electromagnetism, rheology, and mechanical deformation of liquid metal and magnetic particle polymer composites, this work will achieve materials for human facing devices that can effectively improve quality of life without sacrificing performance.