Three-Dimensional Chemical Analysis and Molecular Dynamics Simulations: Application to Flame Retardants in Polymers

三维化学分析和分子动力学模拟：在聚合物中阻燃剂的应用

• 批准号: 0517236
• 负责人: Leslie Butler
• 金额: $ 45万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2009-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0517236&HistoricalAwards=false
• 关键词: Three; Dimensional; Chemical; Analysis; Molecular

Professors Leslie G. Butler and Randall W. Hall of the Louisiana State University and Agricultural and Mechanical College are supported by the Analytical and Surface Chemistry Program in the Division of Chemistry for conducting three- dimensional chemical analysis and molecular simulations with applications to flame retardants in polymers. The application of three-dimensional imaging methods to chemistry is new, thus, methods for image analysis will be developed. Images will be acquired with synchrotron X-ray tomography in a mode that yields elemental concentrations throughout a 2 millimeters cube at a resolution of 3 micrometers. As sample ages, it is expected that good flame retardants dissolve into the polymer and bad flame retardants form internal domains and surface blooms. The diffusion rates, activation energies, and diffusion mechanisms will be measured experimentally and compared with theoretical simulations.Three-dimensional imaging offers new views of chemistry in solids, like the diffusion of molecules through glassy polymers. Computer simulations of glasses can describe the structure and dynamics of glasses and thus diffusion of molecules through a glass. A practical example is the slow (years) diffusion of flame retardants through polymers. Sometimes, the dusty feel on old CRTs and printer cases is caused by the precipitation of flame retardants and is informally called "blooming". A common example of blooming is the diffusion and surface precipitation of cocoa butter on the surface of old chocolate. A web-based tutorial will be created to introduce the students to basic sciences and the three dimensional image analysis aspects of this research.

Leslie G.教授Butler和Randall W.路易斯安那州立大学和农业与机械学院的大厅由化学系的分析和表面化学项目支持，进行三维化学分析和分子模拟，并应用于聚合物中的阻燃剂。 三维成像方法在化学中的应用是新的，因此，图像分析方法将得到发展。 将使用同步加速器X射线断层扫描仪采集图像，其模式为在整个2毫米立方体中以3微米的分辨率产生元素浓度。 随着样品老化，预期好的阻燃剂溶解到聚合物中，而坏的阻燃剂形成内部域和表面霜。 扩散速率、活化能和扩散机制将通过实验测量，并与理论模拟进行比较。三维成像提供了固体化学的新观点，如分子通过玻璃状聚合物的扩散。 玻璃的计算机模拟可以描述玻璃的结构和动力学，从而描述分子通过玻璃的扩散。 一个实际的例子是阻燃剂通过聚合物的缓慢（数年）扩散。 有时候，旧CRT和打印机外壳上的灰尘感是由阻燃剂的沉淀引起的，非正式地称为“起霜”。 起霜的一个常见例子是可可脂在旧巧克力表面的扩散和表面沉淀。 将创建一个基于网络的教程，向学生介绍本研究的基础科学和三维图像分析方面。