NSF East Asia and Pacific Summer Institute (EAPSI) for FY 2013 in Japan

Reeder Jonathan T, Plano TX

Investigators

Abstract

This action funds Jonathan Thomas Reeder of The University of Texas at Dallas to conduct a research project in Engineering during the summer of 2013 at The Someya-Sekitani Organic Transistor Lab at the University of Tokyo in Bunkyo-ku, Tokyo, Japan. The project title is "3D Organic Electronics Enabled by Shape Memory Polymer Substrates." The host scientist is Takao Someya. Flexible electronics that can retain electrical properties through various deformations and can be interfaced with curvilinear surfaces inside the body are enabling biosensors that can read body signals on the chronic time scale by providing enhanced device-tissue interfaces. Flexible transistors based on a high-performance air-stable organic semiconductor were fabricated on a shape memory polymer (SMP) substrate. SMPs are a class of stiffness-changing smart materials that can recover an imparted strain, facilitated by a drop in modulus when heated. This smart polymer substrate and attached thin-film electronics can conform or be adjusted into various shapes by heating the substrate above its glass transition temperature, which is the temperature where the polymer becomes rubbery. Results show that by synthesizing an SMP substrate with a transition temperature near body temperature, organic transistor devices can be fabricated that soften and conform to 3D geometries when exposed to body conditions. This will enable future biomedical devices that are compliant to surrounding tissue and stationary after implantation. The softening nature of the SMP also ensures a reduction in the body?s immune response to the implanted device due to a reduction in the mismatch of stiffness between the implant and body tissue. These air-stable organic electronics have low power requirements and have sufficient electrical properties required to build biosensors or tissue stimulators. SMPs with 3D recovery states which are activated by body conditions are also enabling deployable biosensors that can actively grab or wrap around complex 3D geometries such as nerves, blood vessels, or neural tissue. Broader impacts of an EAPSI fellowship include providing the Fellow a first-hand research experience outside the U.S.; an introduction to the science, science policy, and scientific infrastructure of the respective location; and an orientation to the society, culture and language. These activities meet the NSF goal to educate for international collaborations early in the career of its scientists, engineers, and educators, thus ensuring a globally aware U.S. scientific workforce. This EAPSI fellowship will strengthen an existing collaboration between the University of Tokyo and the University of Texas at Dallas and will facilitate future exchange of researchers and students. Research that will be performed over the summer will be presented at international conferences during the subsequent year, and the broad scope of the proposed research will yield dissemination of results to a broad audience of materials scientists, electrical, mechanical, and biomedical engineers.