This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Using theory and simulation, our goal is to design coatings that permit the controlled spatial-temporal modulation of surface properties and, thereby, impart biomimetic functionality to a broad range of systems. In these studies, we will take advantage of the distinctive behavior of polymer gels undergoing the Belousov-Zhabotinsky (BZ) reaction. The BZ gels are currently the only known polymer networks to display autonomous mechanical oscillations. Furthermore, the BZ reaction is photosensitive and by varying the light intensity, we can manipulate the response of the material. It is this interplay between the chemo-responsive polymer network and the photosensitive reaction that we will exploit to direct the self-sustained movement of the gels. By coating a surface with thin films or tethered filaments of these BZ gels, we can confer to the resulting systems such properties as autonomous sensing, actuation and reconfiguration. In these applications, light provides useful advantages as a control mechanism: it permits a means for remote regulation, is a clean energy source and can be easily turned on or off. If successful, the findings will reveal nonlinear dynamical phenomena that can arise from a coupling of chemical, optical and mechanical energy, and establish design rules for creating millimeter-scale devices that effectively operate under their own power to perform valuable functions. In addition, the study will produce computational models that enable users to design and predict the properties of soft materials that encompass active components. To encourage the participation of more students in undergraduate research and to let undergrads already engaged in research become familiar with the activities of their colleagues, the PI will organize a day-long Undergraduate Research Poster Fair for the nearby universities. Students from local high schools will also be invited to attend. The undergraduate researchers would be particularly effective at relating to this younger cohort and could play an important role in encouraging the 9-12th graders to pursue science and engineering in college.
