(558d) From Nano-Responsive Shapes to Self-Repairing Polymer Networks

Continuous needs for engineering of new materials and devices, with distinct properties and functions that will revolutionize future technologies, require developments of unique and controllable shapes at nano- or smaller length scales. To achieve these attributes, orchestrated heterogeneous regions within engineered polymer networks are necessary for localized structural and morphological variations to occur, thus enabling favorable spatial and energetic conditions for spontaneous responses induced by minute external or internal stimuli. These generalized needs and concepts formulated the principles for the developments of new generations of stimuli-responsive nano-materials/devices and self-repairing networks. This presentation will discuss recent advances in and developments of controllable shape asymmetric nanoparticles, nanotubes, and nanorods, enabling applications in diversified stimuli-responsive devices, ranging from unique optical properties to cilia-like behavior, or nano-tubes assembled to function as oxygen generating reactors. Orchestrated network heterogeneities below nano-scale lengths provided an opportunity for the development of self-healing polyurethane networks that upon mechanical damage and subsequent exposure to UV light, exhibit self-repairing attributes via free radical crosslinking. Using a combination of spectroscopic and thermo-mechanical analytical tools the correlation between molecular changes and macroscopic network remodeling will be discussed.