SGER: Breaking the Size-Threshold for Thermal Analysis of Polmer Thin-films: NanoDSC

技术概述：聚合物在非常小的纳米尺度上具有不同寻常的性质。以薄膜、小孔隙或岛屿的形式对材料的空间限制会对其热力学性质产生巨大影响。近年来，一些实验表明，空间约束对聚合物的玻璃化转变温度Tg有很大的影响。空间约束对于由自组装单层膜（SAM）组成的薄膜也很重要。此外，在非常快的加热/冷却速率下加工聚合物也会对材料性能产生巨大影响。商用差示扫描量热计（DSC）是一种常用的分析研究高分子材料的工具。不幸的是，传统的DSC仪器不能用于这些类型的实验，因为它们缺乏灵敏度和扫描速率太慢。然而，最近出现了一种新的量热技术——纳米量热法，它能够以极快的冷却/加热速度测量极小的样品。本研究的重点是利用NanoDSC研究薄膜聚合物玻璃化转变温度的空间限制和sam的热力学性质。本研究将开发在扫描冷却循环中测量热容量的方法，并弥补传统DSC的慢扫描速率和纳米量热法的快扫描速率之间的差距。非技术总结：这项研究很重要，因为下一代材料技术的许多进步有望通过在纳米尺度上制造和操纵材料来实现。这项研究将提供在如此小的微观水平上检查材料所需的基本工具，从而允许使用传统技术分析现在无法获得的材料。这项研究的影响是增加了该国的基础科学基础设施以及关键研究领域的技术。纳米量热法在纳米技术的广泛表征需求中特别有用，在聚合物、微电子和生物医学工业中也特别重要。这项研究的广泛影响将包括纳米技术领域研究生的教育和培训。纳米热法已经产生了国际合作，这项研究将增加这方面的努力。

TECHNICAL SUMMARY:Polymers have unusual properties when confined to very small nanometer-scale dimensions. Spatial confinement of materials in the form of thin films, small pores, or islands can have a dramatic effect on their thermodynamic properties. Recently, some experiments have shown that spatial confinement can have a large effect on the glass transition temperature Tg for polymers. Spatial confinement is also important for thin films consisting of self-assembled monolayers (SAM). In addition, processing polymers at very fast heating/cooling rates also has a dramatic effect of the material properties. Commercial differential scanning calorimeters (DSC) are the tools often used for analysis investigations of polymer material. Unfortunately, conventional DSC instruments can not be used for these type of experiments because they lack sensitivity and have scan rates which are too slow. However recently a new calorimetry technique Nanocalorimetry has been developed which has the capability of measuring extremely small samples at extremely fast cooling/heating rates. This proposal focuses on using the NanoDSC to investigate spatial confinement of the glass transition temperature of thin film polymers and the thermodynamic properties of SAMs. This research will develop methods to measure heat capacity during the cooling cycle of a scan and bridge the gap between the slow scan rates of conventional DSC and the fast rates of Nanocalorimetry.NON-TECHNICAL SUMMARY:This research is important because much of the advances in materials technology in the next generation are expected to be made by fabricating and manipulating materials at the nanometer scale dimensions. The research will provide the fundamental tools needed to examine materials at such small microscopic levels and thus allowing analysis of material that is now inaccessible when using conventional techniques. The impact of this research is to add to the infrastructure of the country for basic science as well as for technology in a critical research area. Nanocalorimetry will be especially useful in a wide range of characterization needs in nanotechnology and will be particularly important in the polymer, microelectronic, and biomedical industries. The broad impact of this research will include the education and training of graduate students in the field of nano-technology. Nanocalorimetry has already generated international collaborations and this research will increase this effort.