NIRT: Dimension Dependent Material Properties of Nanoscopic Macromolecular Structures

最近的工作已经确定，聚合物材料的质量传输和玻璃化转变行为可以在纳米级结构中与在本体中显著不同。在这种情况下，结构被定义为物理构造（例如，膜、线或柱）。这些差异的起源并不清楚，这是一个相当有争议的问题。关于纳米结构的机械性能知之甚少，尽管正是这些性能对未来纳米纤维工艺的成功提出了最直接和最重大的挑战。PI将对纳米结构中聚合物材料的热物理性能进行全面研究，包括运输和机械行为。这项工作旨在阐明和建立在这种结构中的聚合物的物理和热行为的一般原则。为此，将开发和改进能够大规模生产尺寸为数十纳米的纳米级图案的先进光刻技术。由此产生的实验结构将允许在这项工作中设想的大规模表征工作。将开发新的实验策略来测量机械性能和表征机械行为。单分子，光漂白和其他光谱实验将追求建立动力学和力学之间的联系。分子模拟方法将被开发和实施，用于纳米级聚合物结构的分子和多尺度模拟;这些将被用来解释和合理化我们的实验工作的结果。它将具有相当大的科学价值，因为它将提供在基础水平上理解软物质先进材料所需的大量数据和见解。它将具有相当大的技术影响，因为它将帮助半导体和纳米纤维工业的目标材料，工艺和策略，以制造用于集成电路，光子学，传感器，纳米机电系统，和纳米生物技术。研究活动将大大利用校园内的纳米技术中心和材料研究科学与工程中心这些中心将提供最先进的纳米制造和表征设施，这是必不可少的拟议的实验。一个积极的教育和推广计划将积极推行，使纳米技术的大学预科学生，教师和公众。通过与威斯康星州大学现有的全国知名教育项目的合作，将有可能在讲座，交流计划和实习（学生和教师），教学材料开发，网站和参与科学技术博物馆中传播NIRT赠款的活动和结果。

Recent work has established that the mass transport and glass transition behavior of polymeric materials can be significantly different in nanoscopic structures than in the bulk. A structure in this case is defined as a physical construct (e.g. a film, a line, or a post). The origin of these differences is not well understood, and it is a subject of considerable debate. Less is known about the mechanical properties of nanoscopic structures, although it is precisely these properties that pose the most immediate and significant challenges to the success of future nanofabrication processes.The PI will conduct a comprehensive study of the thermophysical properties, including transport and mechanical behavior, of polymeric materials in nanoscopic structures. The work seeks to elucidate and establish the general principles that govern the physical and thermal behavior of polymers in such structures. To that end, advanced lithographic techniques capable of mass-producing nanoscopic patterns with dimensions on the scale of tens of nanometers will be developed and refined. The resulting experimental structures will permit the large-scale characterization effort envisaged in this work. Novel experimental strategies will be developed to measure mechanical properties and characterize mechanical behavior. Single-molecule, photobleaching and other spectroscopic experiments will be pursued to establish the connections between dynamics and mechanics. Molecular modeling methods will be developed and implemented for molecular and multi-scale simulations of nanoscopic polymeric structures; these will be used to interpret and rationalize the results of our experimental work.The results generated by this NIRT will fill a serious gap in nanoscience. There will be considerable scientific value in that it will provide much of the data and insights required to understand soft-matter advanced materials at a fundamental level. It will be of considerable technological impact in that it will help the semiconductor and nanofabrication industries target materials, processes, and strategies to manufacture deep sub-100 nm structures for integrated circuits, photonics, sensors, nanoelectromechanical systems, and nanobiotechnology.The research activities will be leveraged considerably by the existence on campus of a Center for Nanotechnology and a Materials Research Science and Engineering Center. These centers will provide access to state-of-the-art nanofabrication and characterization facilities, which are essential for the proposed experiments.A vigorous education and outreach program will be aggressively pursued to bring nanotechnology to pre-college students, teachers and the general public. Through a collaboration with existing, nationally-renowned educational programs at the University of Wisconsin, it will be possible to disseminate the activities and results of the NIRT grant in lectures, exchange programs and internships (for both students and teachers), instructional material development, a web site, and participation in science and technology museums.