Structure and Dynamics of Polymer Nanocomposite Materials

聚合物纳米复合材料的结构与动力学

• 批准号: 9973933
• 负责人: Robert Vold
• 金额: $ 37.5万
• 依托单位: College of William and Mary
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-15 至 2003-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9973933&HistoricalAwards=false
• 关键词: Structure; Dynamics; Polymer; Nanocomposite; Materials

9973933VoldNanocomposites are a novel class of materials whose microscopic architecture is controlled by design over distance scales from tens to hundreds of nanometers. These spatial dimensions are larger than thoserelevant to ordinary chemical synthesis, but much smaller than those accessible by macroscopic engineering techniques. Nanocomposite materials often exhibit exciting new properties which arise from their special architecture, but their synthesis is still largely a matter of trial and error. In part, this arises because techniques for characterizing nanostructures need to be improved. In particular, while many techniques can reveal geometric features of nanostructures, there are not many techniques available for studying molecular motion in these complex materials.By focusing attention on specific materials which have potentially important technological applications, the proposed work will illustrate the practical utility of solid state NMR as a tool to aid tailoring the properties of composite materials to achieve specific design goals. Two representative projects are discussed in detail, one dealing with polymer/clay nanocomposites and other with dendridic polymers. One novel aspect of the proposed work is it's emphasis on molecular motion. This is important because bulk material properties such as strength, toughness, resistance to thermal and chemical degradation, and chemical selectivity are all dependent not only on static structure, morphology and supramolecular architecture, but also on the microscopic mobility of the molecular subunits. The work described in this proposal will apply modern techniques of solid state nuclear magnetic resonance as a tool for characterizing both structure and dynamics in nanocomposites. This is important because a detailed understanding of both static structure and molecular dynamics is needed to guide the rational design of new materials with optimized macroscopic properties.

9973933 Vold纳米复合材料是一类新型材料，其微观结构是由设计控制的距离尺度从几十到几百纳米。 这些空间维度比普通的化学合成要大，但比宏观工程技术要小得多。 纳米复合材料通常表现出令人兴奋的新特性，这些特性源于其特殊的结构，但它们的合成在很大程度上仍然是一个试验和错误的问题。 在某种程度上，这是因为表征纳米结构的技术需要改进。 特别是，虽然许多技术可以揭示纳米结构的几何特征，有没有太多的技术可用于研究分子运动在这些复杂的material.By专注于特定的材料，具有潜在的重要技术应用，拟议的工作将说明的实际效用的固态NMR作为一种工具，以帮助定制的复合材料的性能，以实现特定的设计目标。 两个代表性的项目进行了详细讨论，一个处理聚合物/粘土纳米复合材料和其他树枝状聚合物。 这项工作的一个新方面是它强调分子运动。 这是重要的，因为本体材料的性质，如强度，韧性，耐热性和化学降解性，以及化学选择性都不仅取决于静态结构，形态和超分子结构，而且还取决于分子亚基的微观流动性。 本提案中描述的工作将应用现代固态核磁共振技术作为表征纳米复合材料结构和动力学的工具。 这一点很重要，因为需要详细了解静态结构和分子动力学，以指导具有优化宏观性能的新材料的合理设计。