Role of Interface Interpenetration and Domain Size on Dynamic Coupling Across Dissimilar Polymer Domains

非技术概述：用于离子传导、过滤、光电发电或复合增强等技术应用的先进材料设计侧重于在纳米级结合不同的材料成分。这就创建了这样的系统，其中几乎所有部件都位于界面附近，因此所产生的性能主要取决于这些界面附近的本地材料属性。最近的观察表明，在最终材料加工和界面形成过程中建立的不同聚合物界面之间存在着意想不到的强烈动力学耦合。这项计划中的研究旨在了解是什么控制了不同聚合物结构域之间的动态耦合，以及界面是如何调节这种行为的。使用一系列不同技术的简化系统上的实验将被用来研究在界面形成过程中多层系统中发生了什么性质变化，以及它们如何改变整个材料的动力学。与这项研究相结合的将是对学生的教育以及外联。国际和平协会的外联工作包括与埃默里的卡洛斯博物馆教育项目合作，为教师和学校团体开发STEAM(科学、技术、工程、艺术和数学)方案，涵盖古代文化使用的科学概念，如历史水资源管理战略。与博物馆首席保管员合作，本科生研究项目将表征聚合物树脂及其在艺术品保护中的应用。技术摘要：计划中的研究旨在了解是什么控制了不同聚合物结构域之间的动态耦合，以及界面如何调节这种行为。我们将使用一系列不同的技术在简化的系统上进行实验，以研究在界面退火过程中多层系统中发生的性质变化，这些变化会改变材料的动力学。在给定的系统上使用多种实验技术的结果的比较将提供有关现象的更全面的图景，从而促进更好的理解。对不同厚度的多层膜的实验将使用以下技术：石英晶体显微镜，以研究渐变界面退火时横波在不同聚合物界面上传播的变化；椭偏仪，以研究玻璃-橡胶聚合物界面影响下物理老化的变化；以及差示扫描量热法，以比较玻璃化转变宽度和随温度变化的热容。这些技术的结果将与在等效系统上使用荧光对玻璃转变温度的局部深度相关测量进行关联或对比。该项目的目标是解决在界面形成过程中哪些可实验测量的因素发生变化，从而导致不同聚合物区域之间的动态耦合，以及有限区域大小(改变边界条件)如何改变这一现象。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL SUMMARY:Advanced materials design for technological applications such as ion conduction, filtration, photoelectric generation, or composite reinforcement is focused on combining different material components at the nanoscale level. This creates systems where nearly all parts are near an interface making the resulting performance primarily dependent on the local material properties near these interfaces. Recent observations have demonstrated an unanticipated strong coupling of dynamics across dissimilar polymer interfaces established during final materials processing and interface formation. The planned research aims to understand what controls this dynamical coupling across dissimilar polymer domains and how interfaces mediate this behavior. Experiments on simplified systems using a series of different techniques will be carried out to investigate what property changes take place in multilayer systems during interface formation and how they alter the dynamics across the material. Integrated with this research will be education of students as well as outreach. Outreach efforts by the PI involve a partnership with Emory's Carlos Museum education programs to develop STEAM (Science, Technology, Engineering, Arts and Mathematics) programing for teachers and school groups covering scientific concepts used by ancient cultures such as historical water management strategies. In collaboration with the Museum's Chief Conservator, undergraduate research projects will characterize polymer resins and their applications used in artwork conservation. TECHNICAL SUMMARY:The planned research aims to understand what controls dynamical coupling across dissimilar polymer domains and how interfaces mediate this behavior. Experiments on simplified systems using a series of different techniques will be carried out to investigate what property changes take place in multilayer systems during interface annealing that alter the dynamics across the material. Comparison of results using multiple experimental techniques on a given system will provide a fuller picture of the relevant phenomena and thus facilitate improved understanding. Experiments on multilayer films with varying layer thicknesses will be done using the following techniques: quartz crystal microscopy to investigate changes in shear wave propagation across dissimilar polymer interfaces upon progressive interface annealing, ellipsometry to study changes in physical aging due to the impact of glassy-rubbery polymer interfaces, and differential scanning calorimetry to compare glass transition breadths and temperature-dependent heat capacities. Results from these techniques will be correlated or contrasted to localized depth-dependent measurements of the glass transition temperature using fluorescence on equivalent systems. The goals of this project are to address which experimentally measurable factors change during interface formation leading to dynamical coupling between different polymer domains, and how finite domain sizes (changing boundary conditions) alter this phenomenon. .This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.