Woodruff School of Mechanical Engineering
Faculty Candidate Seminar
Mechanics and Physics of Shape Memory Polymers
Dr. H. Jerry Qi
University of Colorado at Boulder
Tuesday, March 26, 2013 at 3:00:00 PM
MRDC Building, Room 4211
Reconfigurable multifunctional structures, which allow combined changes of shape, functionality and mechanical properties on demand, require new adaptive materials that permit modulation of mechanical properties in an effective manner. Shape memory polymers (SMPs) are a unique class of smart materials that can “memorize” their permanent (equilibrium) shape, be temporarily fixed in non-equilibrium shapes, and recover their permanent shape on command when exposed to heat, light, or other external stimuli. Because polymers are intrinsically soft, SMPs allow much larger shape change than other smart materials, such as shape memory alloys and piezoelectric materials. This makes them good candidates for the applications of reconfigurable multifunctional structures. In this presentation, we first introduce the basic concept in SMPs along with some recent exciting developments, such as semi-crystalline polymer based two-way SMP, isotropic and anisotropic shape memory elastomeric composites, and light activated polymers. We then focus on the two types of the physical mechanisms underlying the shape memory and actuations of these materials and discuss the development of physics-based finite deformation constitutive models. In addition, we present using these models to assist the designs of some SMP-based applications. Finally, future works on developing models and material applications for shape memory polymers are discussed.
Dr. Qi is an Associate Professor in the Department of Mechanical Engineering at University of Colorado (CU) at Boulder. He is also a fellow and executive committee member of newly established interdisciplinary Material Science and Engineering Program at CU Boulder. He received his bachelor and graduate degrees in Engineering Mechanics from Tsinghua University, Beijing, China, and received his doctor degree in Mechanical Engineering from Massachusetts Institute of Technology (MIT) in 2003. Prior to joining CU-Boulder in 2004, he did a one-year post-doctoral research at MIT. His current research is in the area of mechanics of soft materials, with a focus on soft active materials, including theoretical and experimental investigation of structure-function relationships of shape memory polymers and elastomers, and arterial tissues. In 2005, he received the Junior Faculty Development Award from University of Colorado at Boulder. In 2007, he received the CAREER award from NSF.
Refreshments will be served.