Collaborative Research: Molecular Structure and Phase Separation Behavior of Novel Phosphate-glass / Polymer Hybrids Studied by Advanced Solid-state NMR and Rheometry Methods

非技术描述：这项工作的结果将在全国发挥重要作用。为新的和现有的应用开发先进材料的兴趣。预计这些材料将具有许多理想的特性，这将使它们具有有用的应用，例如用于固态电池的固体电解质或用于燃料电池的聚合物电解质膜，以及作为核废料的储存材料。混合材料的易于合成和理想的性能将使它们成为探索驱动无机玻璃和有机聚合物自组装成有用材料的新路线的可行性的优秀模型系统，使它们得到广泛应用。该项目将为研究生提供研究培训，并将利用爱荷华州立大学、苏黎世联邦理工学院和桑迪亚国家实验室（SNL）的互补专业知识和研究资源。该项目还将通过学习跨学科基础知识如何用于解决实际问题来促进研究生的职业发展。研究人员通过现有的nsf支持的美国-瑞士研究合作建立了牢固的工作关系，并与SNL合作，将为项目的相关性提供关键指导和明确的重点。南密西西比大学有相当数量的少数族裔学生，他们可以从材料科学和工程的广泛领域的培训中受益。技术细节：这个跨学科合作研究项目的最终目标是更好地理解低tg无机磷酸盐-玻璃(Pglass)/聚合物杂化体系中控制相分离动力学、热流变学和结构形成的基础科学，并确定基本分子结构和杂化物流变性能之间关系的准确预测模型。这是建立合理的合成和设计原则的第一步，指导新的杂化材料的合成和加工。通过多种实验方法，如先进的固态核磁共振和热流变技术，研究人员提出了解Pglass相分离行为及其对新型低tg无机Pglass/聚合物杂化材料微观结构的影响，并确定这类新型杂化材料的技术潜力。从这些研究中获得的结果将用于测试文献中关于简单聚合物系统的相分离和自组装的现有理论是否适用，并可能减少或消除文献和工业中常见的昂贵的“试错”做法。此外，将使用和改进先进的固态核磁共振方法，可靠地测量和表征分子和纳米尺度上的杂化结构和相互作用。为了避免先前的尝试进展缓慢，主要是在工业中，遵循一种方法而忽略其他方法，本提案结合了三种方法来合理设计和合成材料（即，在分子水平上，通过材料加工和表面化学）。随着陶瓷材料研究不断与聚合物和光电材料等其他材料重叠，本提案中讨论的方法和合作的多样化应该变得更加重要。液相中杂化组分之间的界面和偶然的混相对流变性和相分离的影响，混合的程度，特别是在相域和尺寸之间的界面，杂化组分之间的有利反应，以及Pglass添加后显著的杂化粘度降低，将是决定许多理想杂化性能的关键。

NON-TECHNICAL DESCRIPTION: The results of this work will play an important role in the nation?s interest in developing advanced materials for new and existing applications. The materials are expected to possess a number of desirable properties that will make them useful applications such as solid electrolytes for solid-state batteries or polymer electrolyte membranes for fuel cells and as storage materials for nuclear wastes. The facile synthesis and desirable properties of the hybrid materials will make them excellent model systems for exploring feasibility of new routes for driving inorganic glasses and organic polymers to self-assemble into useful materials, making them widely applicable. The project will provide research training to graduate students and will also take advantage of complementary expertise and research resources at Iowa State University, ETH Zurich, and Sandia National Laboratories (SNL). The project will also advance the graduate students careers by learning how fundamental interdisciplinary knowledge can be used to solve a practical problem. The strong working relations the investigators have developed via an existing NSF-supported U.S.-Switzerland research cooperation, and with SNL will provide critical guidance and clear focus on relevance of the project. The University of Southern Mississippi has a sizable minority student population who could benefit from training in the broad area of materials science and engineering.TECHNICAL DETAILS: The ultimate goal of this collaborative interdisciplinary research project is to better understand the fundamental science governing the phase separation dynamics, thermorheology, and structure formation in low-Tg inorganic phosphate-glass (Pglass)/polymer hybrid system and to identify accurate, predictive models of relationships between fundamental molecular structures and rheological properties of the hybrids. This is a first step toward establishing rational synthesis and design principles to guide the synthesis and processing of new hybrid materials. By using a variety of experimental methods such as advanced solid-state NMR and thermorheological techniques, the investigators propose to understand the Pglass phase separation behavior and its effect on microstructure of the novel low-Tg inorganic Pglass/polymer hybrid materials, and to identify the technological potential of this new class of hybrid materials. The results obtained from these studies will used to test whether or not existing theories on phase separation and self-assembly reported in the literature on simple polymer systems are applicable, and may reduce or eliminate costly "trial and error" practices common in the literature and industry. In addition, advanced solid-state NMR methods for reliably measuring and characterizing the hybrid structure and interactions on the molecular and the nanometer scale will be used and improved. To avoid disappointingly slow progress in prior attempts, mostly in industry, to follow one approach while neglecting the others, this proposal combines the three approaches to rational design and synthesis of materials (i.e., at the molecular level, by materials processing, and by surface chemistry). The diversification of approach and cooperation discussed in this proposal should become more critical as ceramic materials research continues to overlap other materials such as polymers and electro-optical materials. The interface and the fortuitous miscibility in the liquid state between the hybrid components for the rheology and phase separation, the extent of mixing, particularly at the interface between the phase domains and sizes, the favorable reactions between the hybrid components, and the remarkable hybrid viscosity decrease by the Pglass addition will be critical in determining a number of the desirable hybrid properties.