Nanostructured Surfaces for Investigation of Friction at the Molecular Scale

0202468 Chuang分子相互作用/排列及其与两个接触、移动表面之间的摩擦的关系的知识随着机械工程设备的规模继续缩小到微观和最终纳米尺度而变得越来越重要。 缺乏监测分子相互作用/排列的原位技术不仅对理解摩擦的分子起源提出了挑战，而且还阻碍了新型润滑系统的开发，以最大限度地减少摩擦和磨损。 这个探索性的研究项目提出了一种原位红外光谱技术的发展，以表征分子之间的相互作用/对齐两个接触，移动表面的工作条件下，同时摩擦测量。 接触表面将接枝有含有CF 3、磷酸酯、烷基、芳基、醚和COOH基团的有机分子。 这些不同类型的分子表面允许调查的作用货车der Walls力，疏水/亲水相互作用，极性官能团，和摩擦中的静电相互作用。 在摩擦测量过程中，分子内和分子间相互作用、分子构象、堆积和排列的变化将由分子振动频率的变化来确定。 这一工作有望对运动表面上的摩擦力有一个基本的认识。 这种理解与分子接枝方法相结合，将为开发用于移动表面的永久性超低摩擦涂层提供技术基础。 这种类型的无液体润滑将提供无污染的环境并消除对油的需要（即，润滑剂）变化。 这项研究的结果可能会对纳米结构表面的设计产生深远的影响，这些纳米结构表面用于控制从MEMS设备、人工关节、轴承到齿轮的中、微和宏观移动设备的摩擦。

0202468Chuang Knowledge of molecular interactions/alignment and their relations to friction between two contacting, moving surfaces are becoming important as the scale of mechanical engineering devices continues to shrink to microscopic and eventually nanoscopic scales. A lack of in situ techniques to monitor molecular interactions/alignment not only presents a challenge to understand the molecular origin of friction but also hinders the development of novel lubrication systems to minimize friction and wear. This exploratory research project proposes the development of an in situ infrared spectroscopic technique to characterize molecular interactions/alignment between two contacting, moving surfaces under working conditions with simultaneous friction measurement. The contacting surfaces will be grafted with organic molecules containing with CF3, phosphate, alkyl, aryl, ether and COOH groups. These various types of molecular surfaces allow investigation of the role of van der Walls forces, hydrophobic/hydrophilic interactions, polar functional groups, and electrostatic interactions in friction. Changes in intra- and intermolecular interactions, molecular conformation, packing, and alignment during friction measurement will be determined by the shift in molecular vibrational frequencies. This work is expected to develop a fundamental understanding of ghe friction on the moving surfaces with the well-defined molecular arrangement. This understanding coupled with the molecular grafting approach will provide a technical basis for the development of permanent, ultra low-friction coatings for moving surfaces. This type of liquid-free lubrication will provide a contaminant-free environment and eliminate the need for oil (i.e., lubricant) change. The results of this proposed study could have a far-reaching impact on the design of nanostructured surfaces for controlling friction for meso-, micro-, and macroscopic moving devices ranging from MEMS devices, artificial joints, bearings, to gears.