Proposal Number: CTS-0438389 Principal Investigator: Abramson, Alexis R Affiliation: Case Western Reserve University Proposal Title: Coupled Thermal and Mechanical Behavior of Conducting Polymer Nanostructures
Conducting polymer nanostructures have gained attention by the nanoelectronics community because of their high electrical conductivity, mechanical flexibility and potential for low-cost manufacturing. Moreover, the properties of these nanosized polymer structures make them interesting candidates for additional applications such as for membrane materials, tissue scaffolding, sensing, and in composite materials. Improved characterization of coupled thermal and mechanical response of these nanostructures is expected to lead to a better understanding of the novel phenomena at the nanoscale that is essential to the nanoelectronics industry as well as for current and future applications. In view of the lack of understanding of the coupling between mechanical strain and thermal transport in conducting polymer nanostructures and the scientific and technological importance of the successful implementation of these materials to society, a collaborative three year multidisciplinary research effort comprising specialists in polymer processing/nanofabrication, transport properties at the nanoscale, and experimental nanomechanics is being proposed. The research will integrate three major ingredients, i.e. synthesis and nanofabrication, experimentation and modeling. The proposed research will focus on the behavior of thermal and mechanical properties (both coupled and uncoupled) of conducting polymer nanostructures as a function of temperature. Polyaniline nanostructures with different shape, size, morphology, and porosity will be investigated. The polymer nanostructures will be nanofabricated using a wet electropolymerization process. The design and development of a novel testing device will enable coupled mechanical and thermal measurements of the polyaniline nanostructures. This nano-tensilometer device is based on a novel modification to the commercially available Hysitron triboindenter and will be combined with specialized thermal probes. The device will be used inside a high resolution scanning electron microscope (SEM) with in-situ nanomanipulators. An electron-beam induced deposition (EBID) procedure will be employed to "nanoweld" the nanostructures to the probe tips or micro-device. A theoretical analysis will be utilized to complement experimental results and enable an improved understanding. It is emphasized that the proposed research program is innovative and novel and entails considerable nanofabrication, experimental and modeling challenges. It represents a major departure from the conventional and current techniques employed by the energy transport and experimental mechanics communities to investigate coupled thermal/mechanical behavior in micro- and/or nanoscale structures. A strong learning and teaching component, integral to the research objectives, will provide for significant educational enhancement for both undergraduate and graduate students and will provide for outreach opportunities for K-12 students. These students will greatly benefit from the inherently multidisciplinary nature of this project. Furthermore, they will have the opportunity for laboratory experience on and/or exposure to state-of-the-art modern instrumentation and cutting-edge research. In addition to the involvement of graduate students through their own research projects, CWRU strongly encourages the involvement of undergraduate students in faculty research projects through senior projects and/or laboratory courses. All involved students will be encouraged to participate in national conferences. Attention will also be paid towards the recruitment of underrepresented minority students. Furthermore, the PIs will contribute significant content from this research to the "Nanopedia," an extensive multi-faceted web-based learning approach to nanotechnology curriculum currently under development at CWRU. This resource will be available to university level and K-12 students as well as the general public.
