Coupled Thermal and Mechanical Behavior of Conducting Polymer Nanostructures

国家科学基金会提案编号：CTS-04389主要研究员：艾布拉姆森，亚历克西斯隶属：凯斯西储大学提案标题：导电聚合物纳米结构的热和机械耦合行为导电聚合物纳米结构因其高导电性、机械灵活性和低成本制造潜力而受到纳米电子界的关注。此外，这些纳米聚合物结构的性质使它们成为膜材料、组织支架、传感和复合材料等其他应用的有趣候选者。对这些纳米结构的热和机械耦合响应特性的改进有望在纳米尺度上更好地理解这些新现象，这对纳米电子工业以及当前和未来的应用都是至关重要的。鉴于对导电聚合物纳米结构中机械应变和热传输之间的耦合以及这些材料的成功应用对社会的科学和技术重要性缺乏了解，正在提议一项由聚合物加工/纳米制造、纳米尺度的传输特性和实验纳米力学方面的专家组成的为期三年的多学科合作研究工作。这项研究将整合三个主要组成部分，即合成和纳米制造、实验和建模。拟议的研究将集中在导电聚合物纳米结构的热性能和机械性能(耦合和非耦合)随温度的变化规律。不同形状、大小、形态和孔隙率的聚苯胺纳米结构将被研究。聚合物纳米结构将使用湿法电聚合过程进行纳米细化。一种新型测试设备的设计和开发将使聚苯胺纳米结构的力学和热学测量成为可能。这种纳米张力计设备是基于对市售Hysitron摩擦压力仪的一种新改进，并将与专门的热探头相结合。该装置将用于具有原位纳米操纵器的高分辨率扫描电子显微镜(SEM)中。电子束诱导沉积(EBid)将被用来将纳米结构“纳米化”到探针尖端或微器件上。理论分析将用于补充实验结果，并使人们能够更好地理解。强调指出，拟议的研究计划是创新和新颖的，需要进行相当大的纳米制造、实验和建模挑战。它与能量传输和实验力学领域研究微观和/或纳米尺度结构中的热/力学耦合行为的传统和当前技术有很大的不同。作为研究目标的一个强大的学习和教学部分，将为本科生和研究生提供显著的教育促进，并将为K-12学生提供扩展机会。这些学生将从这个项目固有的多学科性质中受益匪浅。此外，他们还将有机会获得关于最先进的现代仪器和尖端研究的实验室经验和/或接触到这些经验。除了研究生通过自己的研究项目参与之外，CWRU还大力鼓励本科生通过高级项目和/或实验室课程参与教师研究项目。将鼓励所有参与的学生参加全国性的会议。还将注意招收代表性不足的少数族裔学生的问题。此外，PIS将为“纳米百科”贡献重要的研究内容，这是CWRU目前正在开发的纳米技术课程的一种广泛的、多方面的基于网络的学习方法。这一资源将向大学和K-12年级的学生以及普通公众开放。

ABSTRACTNational Science FoundationProposal Number: CTS-0438389Principal Investigator: Abramson, Alexis RAffiliation: Case Western Reserve UniversityProposal Title: Coupled Thermal and Mechanical Behavior of Conducting Polymer NanostructuresConducting 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.